Correct Option (D)
Article 253 of the Indian Constitution empowers Parliament to make any law for the whole or any part of the territory of India for implementing any treaty, agreement, or convention with any other country or any decision made at any international conference, association, or other body. This provision allows the Union government to fulfill its international obligations without requiring the consent of individual states. This legislative power is crucial for maintaining India's standing in international relations and ensuring compliance with global commitments.
Incorrect Options:
Options A, B, and C are incorrect because they suggest that the consent of states, whether all, a majority, or those concerned, is required for Parliament to enact laws implementing international treaties. This contradicts Article 253 of the Constitution, which explicitly grants Parliament this power without such a prerequisite. Requiring state consent would introduce significant procedural hurdles and potentially undermine the Union's ability to conduct foreign policy and honor international agreements effectively. The constitutional framework prioritizes the Union's authority in matters of international relations.