Explanation:

Let’s break it down:

- Under Indian law, specifically Section 375 of the Indian Penal Code, sexual intercourse by a man with his own wife is not considered rape if the wife is above 18 years of age.

- Option 1 says 18 years. That matches exactly what the law says right now.

- Option 2 says 15 years. This used to be the minimum age before, but the law changed after the 2017 Supreme Court judgment. So, it’s outdated now.

- Option 3 says 16 years. Not relevant—the law has never made this the age cut-off for this specific exception.

- Option 4, “None of the above,” isn’t right, since option 1 is correct.

So, the correct answer is Option 1: 18 years of age.