The correct answer is: d) 1972.
Manipur became a full-fledged state of India on 21 January 1972. It was previously a princely state under the British Raj. After India’s independence in 1947, Manipur became a part of the Indian Union on 15 October 1949. However, it continued to have a special status under the Indian Constitution. It was only in 1972 that Manipur was granted full statehood.
The other options are incorrect. Option a) is incorrect because Manipur became a part of the Indian Union in 1949, not 1948. Option b) is incorrect because Manipur became a full-fledged state of India in 1972, not 1956. Option c) is incorrect because Manipur did not become a full-fledged state of India in 1962.