The correct answer is Option 1: 1 and 2 only. Let`s analyze each statement to understand why.

Statement 1: "It is a form of limited government." This statement is correct. Constitutional government refers to a system where the powers of the government are limited by a constitution, which outlines the rights and responsibilities of the government and its citizens.

Statement 2: "One where the Constitution is the basis of public authority." This statement is also correct. In a constitutional government, the constitution serves as the foundation of public authority and establishes the principles, structures, and powers of the government.

Statement 3: "One where the Monarch is the formal Head of the State." This statement is incorrect. Constitutional governments can take various forms, and not all of them have a monarch as the formal head of state. For example, in many constitutional monarchies, the monarch may have ceremonial duties but limited political power.

Statement 4: "One where there is always universal adult franchise." This statement is not mentioned in the question, so we cannot determine its correctness.

To summarize, statements 1 and 2 are correct, statement 3 is incorrect, and statement 4 is not mentioned. Therefore, the correct answer is Option 1.