Correct Answer: 52nd

Solution : The correct option is 52nd.

The 10th Schedule of the Constitution of India, commonly known as the " Anti-Defection Law" was inserted by the 52nd Amendment Act of 1985. The amendment came into effect on March 1, 1985. The purpose of the Anti-Defection Law is to curb the practice of legislators changing their party affiliations for reasons such as seeking personal gains or political opportunism.