Explanation:

- Insanity: Under the Hindu Marriage Act, 1955, if a spouse suffers from an incurable mental disorder or insanity, it is considered a valid ground for divorce.

- Leprosy: Previously a ground for divorce under the Act, leprosy is no longer considered a valid reason due to the repeal of Section 13(iv) with the Marriage Laws (Amendment) Act, 2019.

- Epilepsy: Initially a ground for divorce, it was removed from the list with the Marriage Laws (Amendment) Act, 1976.

- Venereal Disease: If a spouse is suffering from a communicable venereal disease, it could be a valid ground for divorce.

Answer: Option 3 - Epilepsy is not a ground for divorce anymore.