Which of the following Constitutional Amendments are related to raising the number of Members of Lok Sabha to be : elected from the States?

The Constitution (Seventh Amendment) Act altered the population‑per‑seat limits in Article 81(1)(b), thereby relaxing numerical constraints on representation and enabling adjustment of the number of Lok Sabha members to be elected from the States. The Constitution (Thirty‑first Amendment) Act, 1973 explicitly increased the number of elected seats in the Lok Sabha from 525 to 545, concretely raising the House’s strength [1]. Together, the Seventh Amendment provided the permissive change in apportionment norms and the Thirty‑first implemented an increase in elected membership, so the pair of amendments relevant to raising elected Lok Sabha seats from the States is 7th and 31st (option 3).

Sources

1. [1] Introduction to the Constitution of India, D. D. Basu (26th ed.). > Chapter 35: TABLES > THE CONSTITUTION AMENDMENT ACTS > p. 515