CDS I General Knowledge 2021: Complete Question Paper Analysis & Preparation Strategy

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Subject-wise Distribution

SubjectQuestionsPercentage
Science & Technology3226.7%
Economy2218.3%
History & Culture2218.3%
Polity & Governance1915.8%
Geography1815%
International Relations & Global Affairs54.2%
Miscellaneous & General Knowledge10.8%
Environment & Ecology10.8%

Topic-wise Breakdown

SubjectTopicQuestions
Science & TechnologyBasic Science (Physics, Chemistry, Biology)28
History & CultureNational Movement (1857–1947)8
History & CultureModern India (Pre-1857)8
GeographyWorld Physical Geography7
EconomySchemes, Inclusion & Social Sector6
EconomyMoney, Banking & Inflation4
GeographyMaps & Locations4
GeographyIndian Physical Geography4
Polity & GovernanceParliament4
EconomyAgriculture & Rural Economy3
International Relations & Global AffairsIndia's Bilateral & Regional Relations3
Polity & GovernanceFundamental Rights, DPSP & Fundamental Duties3
Polity & GovernanceUnion Executive3
Polity & GovernanceConstitutional & Statutory Bodies3
EconomyGovernment Finance & Budget2

Decoding CDS I 2021: A Masterclass in Strategic Preparation for UPSC Aspirants

The Combined Defence Services (CDS) examination is not merely a test of knowledge; it is a test of temperament, precision, and strategic depth. As an expert mentor who has tracked the evolution of UPSC patterns for over a decade, I view the CDS I 2021 General Knowledge paper as a watershed moment. This paper moved away from rote memorization and firmly planted its feet in the realm of conceptual clarity and interdisciplinary linking. With 120 questions to be tackled in 120 minutes, and the looming shadow of one-third negative marking, this paper served as a wake-up call for those relying solely on superficial guidebooks.

Analyzing this specific paper is crucial because it sets the template for the "New Normal" in UPSC defense exams. In this comprehensive guide, we will dissect every layer of the CDS I 2021 paper, providing you with a roadmap that transforms your preparation from a chaotic sprint into a calculated marathon. Whether you are a first-timer or a seasoned aspirant, understanding the nuances of this paper will be the difference between meeting the sectional cutoff and soaring past the merit list.

Subject-wise Deep Dive: Where the Battle was Won

The 2021 paper was characterized by a heavy tilt toward Science and a sophisticated approach to History and Economy. Let’s break down the core pillars of the syllabus based on the 2021 distribution.

Science & Technology: The Heavyweight Champion

In 2021, Science & Technology dominated the landscape with 32 questions, accounting for a massive 26.7% of the paper. Unlike previous years where questions were direct, 2021 focused heavily on Basic Science (Physics, Chemistry, and Biology), contributing 28 of those questions. The focus was on application-based concepts from NCERTs—refraction, chemical reactions in daily life, and cellular biology.

  • Recommended Books: NCERT Class 9 and 10 (Science) are your bibles. For advanced concepts, refer to selective chapters of Class 11 and 12 Biology (last four chapters for Ecology).
  • Common Mistakes: Ignoring the "boxes" and "activity" sections in NCERTs. Many questions in 2021 were derived directly from these practical examples.

Economy: The Conceptual Gatekeeper

With 22 questions (18.3%), Economy emerged as a significant decider. The focus was remarkably specific: Schemes, Inclusion, and the Social Sector (6 questions) and Money, Banking, and Inflation (4 questions). This indicates that the examiner expects you to understand how the Indian economy breathes, rather than just knowing GDP figures.

  • Recommended Books: Indian Economy by Ramesh Singh for conceptual depth, and the Economic Survey (Summary) for current data.
  • Common Mistakes: Focusing too much on theoretical definitions and ignoring the implementation aspects of government schemes like PM-Kisan or MGNREGA.

History & Culture: The Modern Dominance

History also carried 22 questions, but the distribution was a gift to those who focused on the National Movement (1857–1947) and Modern India (Pre-1857), which together accounted for 16 questions. The examiner moved away from obscure Ancient dates to the socio-political evolution of Modern India.

  • Recommended Books: A Brief History of Modern India (Spectrum) by Rajiv Ahir and the Tamil Nadu State Board Class 11 and 12 textbooks for a chronological flow.
  • Common Mistakes: Over-studying Medieval dates while neglecting the "Why" behind the British administrative changes.

Polity & Governance: The Pillar of Consistency

Polity contributed 19 questions (15.8%), with a sharp focus on the Parliament (4 questions). The questions tested your understanding of the nuances of legislative procedures and constitutional mandates.

  • Recommended Books: Indian Polity by M. Laxmikanth. There is no substitute for this. For a deeper philosophical understanding, Subhash Kashyap’s Our Constitution is excellent.
  • Common Mistakes: Skipping the Preamble, Fundamental Duties, and DPSP. These are "low-hanging fruits" that aspirants often ignore for more complex topics.

Geography: Spatial Awareness

Geography saw 18 questions (15%), with World Physical Geography taking the lead (7 questions). Interestingly, Maps and Locations and Indian Physical Geography both had 4 questions each, highlighting the need for visual learning.

  • Recommended Books: NCERT Class 11 (Fundamentals of Physical Geography) and Certificate Physical and Human Geography by GC Leong.
  • Common Mistakes: Studying Geography without an Atlas. In 2021, those who knew the "where" as well as the "why" scored higher.

Topic Trends & Pattern Analysis: Reading the Examiner's Mind

The CDS I 2021 paper revealed a shift in the UPSC's mindset. The examiner is no longer looking for "walking encyclopedias" but for "analytical thinkers."

The Rise of Applied Sciences

The 28 questions in Basic Science weren't just about definitions. They were about "why does a diamond sparkle?" or "how does a concave mirror behave in a specific scenario?" This tells us that the examiner wants candidates who have a functional understanding of the world around them. This aligns with the requirements of an officer who must handle technology and equipment in the field.

The Shift to Modernity

The heavy weightage on the National Movement (1857-1947) suggests a desire for candidates to be well-versed in the foundational values of the Indian State. If you analyze the 8 questions on Pre-1857 Modern India, they focused on the transition of power, indicating that the examiner values an understanding of administrative and structural changes over mere battle dates.

Comparison with General UPSC Patterns

Much like the Civil Services Examination (CSE), CDS I 2021 showed a "Current-Static Linkage." For instance, if a specific banking reform was in the news, the question asked was about the static concept of SLR or CRR. This "hybrid" questioning style is a hallmark of the modern UPSC examiner.

Preparation Strategy: A Targeted Approach

To conquer a paper like CDS I 2021, your preparation must be surgical. Here is how you should allocate your time and resources:

Subject-wise Time Allocation

  • Science (30% Time): Daily 1 hour of NCERT reading. Focus on the summaries and diagrams.
  • Polity (20% Time): Focus on Laxmikanth. Read one chapter and solve its MCQs the same day.
  • History (20% Time): Focus on the 1857–1947 timeline. Create a wall chart of major events.
  • Geography & Economy (20% Time): Use weekends for map work and reading the Economic Survey.
  • Current Affairs (10% Time): Daily 45 minutes of newspaper reading.

The "Holy Grail" Resource List

Success in CDS is 40% resources and 60% how you use them. Here is your curated list:

  • Polity: M. Laxmikanth is mandatory. For specific chapters like the Judiciary or Parliament, supplement with PRS Legislative Research website for recent bills.
  • History: Use the New NCERTs (Themes in Indian History) for a modern perspective, but keep Spectrum for factual revision.
  • Geography: Use the Orient Blackswan Atlas. For World Physical Geography, GC Leong’s first 10 chapters are indispensable.
  • Economy: Mrunal Patel’s videos or notes are highly recommended for simplifying complex banking and inflation concepts.
  • Environment: While 2021 had only 1 question, don't be fooled. Use Shankar IAS selectively, focusing on National Parks and Biosphere Reserves.

How to Use PYQ Practice Effectively

Don't just "solve" the 2021 paper; "dissect" it. For every question, analyze why the other three options were wrong. If a question is about the 'President of India', go back to your notes and revise the entire 'Executive' section. This is called Reverse Engineering, and it is the fastest way to cover the syllabus.

Answer Elimination Techniques: Winning the MCQ Game

The 2021 paper was designed to trap the over-confident. Elimination is not just a trick; it’s a logic-based strategy.

The "Extreme Words" Trap

In Polity and Economy questions, look for words like "All," "Only," "Never," or "Always." In the 2021 paper, statements containing these were often (though not always) incorrect. UPSC uses these to test if you know the exceptions to the rules.

Statement-based Strategy

For "Consider the following statements" questions, find the one statement you are 100% sure is wrong. Eliminate all options containing that statement. Often, this leaves you with the correct answer immediately, even if you don't know the other statements.

The "Match the Following" Hack

In Geography and History, these are scoring opportunities. Usually, knowing just one correct pair out of four is enough to eliminate two options. From there, your odds of a correct guess jump to 50%.

When to Guess vs. Skip

  • The 50/50 Rule: If you can eliminate two options, you MUST attempt the question. Statistically, over 10 such questions, you will likely come out with a positive score.
  • The "Blind Guess": Never do it. The negative marking in CDS is unforgiving. If you have no clue about any of the four options, move on.

Current Affairs Integration: The Silent Engine

While the data shows only 5 questions for International Relations, the influence of current affairs was visible in almost 40% of the static questions. For example, the focus on Agriculture and Rural Economy (3 questions) was a direct reflection of the ongoing national discourse on farm policies in 2020-21.

Building the Habit

  • The Hindu/Indian Express: Don't read the sports or local news. Focus on the Editorial, Science & Tech, and Economy pages.
  • Monthly Magazines: Yojana is excellent for the Economy and Social Schemes section which saw 6 questions in 2021. Kurukshetra is vital for the Agriculture section.
  • PIB (Press Information Bureau): Check the "Year End Review" of various ministries. This is where UPSC gets its data for government schemes.

Smart Preparation Tips: Planning for Success

Your preparation needs a structure. A 6-month plan is usually the sweet spot for a dedicated aspirant.

The 6-Month Roadmap

  • Months 1-2: Foundation. Complete NCERTs (Science, Geography, History). Don't take notes yet; just understand.
  • Months 3-4: Standard Books. Dive into Laxmikanth and Spectrum. Start making "Micro-notes"—one page for one chapter.
  • Month 5: Integration. Link current affairs with static topics. Start solving topic-wise PYQs.
  • Month 6: The Polish. Solve 10-15 full-length mock tests. Focus on time management and reducing negative marks.

Revision: The 24-7-30 Rule

Revise what you learned today within 24 hours. Revise it again in 7 days. Do a final sweep in 30 days. This moves information from short-term to long-term memory, crucial for the 120-question marathon.

Mock Test Analysis

Spending 2 hours on a mock test is useless if you don't spend 3 hours analyzing it. Track your "Silly Mistakes" vs. "Lack of Knowledge." If you are losing marks to silly mistakes, you need more mocks. If it's lack of knowledge, you need more revision.

Key Takeaways & Action Items

The CDS I 2021 General Knowledge paper teaches us that the UPSC rewards breadth of coverage and clarity of concept. You cannot afford to skip Science, and you must master Modern History and Polity.

Top 5 Books to Prioritize:

  1. NCERT Science (Class 9 & 10): For the 32-question Science block.
  2. Indian Polity by M. Laxmikanth: For the 19-question Polity block.
  3. Spectrum’s Modern History: For the 16-question Modern History block.
  4. NCERT Geography (Class 11 - Physical): For the core Geography concepts.
  5. Economic Survey Summary: For the 6-question Schemes and Social Sector block.

Your Immediate Next Steps:

  • Download the CDS I 2021 GK Question Paper and attempt it in a timed environment without any preparation. This is your "Base Level."
  • Identify your weakest subject from the 2021 distribution. If it's Science or Economy, start there.
  • Buy a high-quality Atlas and start spending 10 minutes every day looking at the physical features of India and the Middle East (a favorite of UPSC).
  • Stop reading multiple sources. Stick to one standard book per subject and revise it five times rather than reading five books once.

The path to the Officers Training Academy (OTA) or the Indian Military Academy (IMA) goes through the General Knowledge paper. While English and Maths are about speed and practice, GK is about strategy and wisdom. Use the insights from the 2021 analysis to work smarter, not just harder. The uniform is not just a dream; with this structured approach, it is a destination. Good luck!

Complete Question Index - CDS I General Knowledge 2021

Click on any question number to practice and view detailed explanation:

Q#SubjectPractice Link
1History & CultureSolve Question 1
1History & CultureSolve Question 1
2International Relations & Global AffairsSolve Question 2
2International Relations & Global AffairsSolve Question 2
3Science & TechnologySolve Question 3
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4GeographySolve Question 4
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5Science & TechnologySolve Question 5
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6EconomySolve Question 6
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7GeographySolve Question 7
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8Science & TechnologySolve Question 8
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9EconomySolve Question 9
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10Science & TechnologySolve Question 10
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11Science & TechnologySolve Question 11
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12International Relations & Global AffairsSolve Question 12
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13Science & TechnologySolve Question 13
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14EconomySolve Question 14
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15Polity & GovernanceSolve Question 15
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16History & CultureSolve Question 16
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17GeographySolve Question 17
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18History & CultureSolve Question 18
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19Polity & GovernanceSolve Question 19
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21Polity & GovernanceSolve Question 21
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22History & CultureSolve Question 22
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23Polity & GovernanceSolve Question 23
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24Miscellaneous & General KnowledgeSolve Question 24
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25History & CultureSolve Question 25
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26Polity & GovernanceSolve Question 26
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27Science & TechnologySolve Question 27
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28GeographySolve Question 28
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30EconomySolve Question 30
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31Polity & GovernanceSolve Question 31
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33History & CultureSolve Question 33
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49Environment & EcologySolve Question 49
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50Polity & GovernanceSolve Question 50
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58GeographySolve Question 58
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62Science & TechnologySolve Question 62
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63History & CultureSolve Question 63
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65GeographySolve Question 65
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72Polity & GovernanceSolve Question 72
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95EconomySolve Question 95
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97GeographySolve Question 97
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98Polity & GovernanceSolve Question 98
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100GeographySolve Question 100
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101Science & TechnologySolve Question 101
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102EconomySolve Question 102
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104History & CultureSolve Question 104
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113Polity & GovernanceSolve Question 113
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115International Relations & Global AffairsSolve Question 115
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119History & CultureSolve Question 119
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