The minimum age for being elected as the President of India is 35 years. This means that a person must be at least 35 years old to become eligible to be elected as the President of India.

Option 1 - 40 years: This is incorrect because the minimum age requirement is 35 years, not 40 years.

Option 2 - 35 years: This is the correct answer. A person must be at least 35 years old to be eligible for the position of President of India.

Option 3 - 30 years: This is incorrect as the minimum age requirement is 35 years, not 30 years.

Option 4 - 25 years: This is incorrect as the minimum age requirement is 35 years, not 25 years.

To summarize, the correct answer is option 2 - 35 years.