Explanation:

- Option 1: 1829

- This is the correct year when Sati was officially banned in India.

- The practice was outlawed by Lord William Bentinck, the then Governor-General of India.

- The Bengal Sati Regulation, or Regulation XVII, was enacted in December 1829.

- Option 2: 1824

- This year is not associated with the ban of Sati.

- There were ongoing debates and movements against Sati around this time, but no legal enforcement occurred.

- Option 3: 1826

- Like 1824, this year did not mark any legal or official ban on Sati.

- Option 4: 1831

- By this time, the practice was already outlawed, so this year is not correct.