The correct answer is (a). The McMahon Line was drawn in 1914. It is a 2,400-kilometer (1,500 mi) border between India and China (Tibet). It was agreed upon by the British and Tibetan governments in the Simla Convention of 1914, but China never accepted the border. The McMahon Line was the subject of a dispute between India and China in the 1962 Sino-Indian War.
Option (b) is incorrect because India and Pakistan gained independence from British rule in 1947. The McMahon Line was already in existence at that time.
Option (c) is incorrect because the Sino-Indian War was fought in 1962. The McMahon Line was the subject of the dispute between India and China during the war.
Option (d) is incorrect because the McMahon Line was drawn in 1914. It was not drawn in 1987.