Which political party played a key role in the movement leading to Sikkim’s merger with India?

The correct answer is: d) Sikkim Praja Sammelan.

The Sikkim Praja Sammelan was a political party in Sikkim that played a key role in the movement leading to Sikkim’s merger with India. The party was founded in 1947 by Kazi Lhendup Dorji and other Sikkimese leaders who were opposed to the rule of the Chogyal, the hereditary ruler of Sikkim. The party campaigned for Sikkim’s independence from India and for democratic reforms. In 1975, the Sikkim Praja Sammelan led a popular uprising against the Chogyal. The uprising was successful, and Sikkim became an Indian state in 1975.

The other options are incorrect.

• The Sikkim National Congress was a political party in Sikkim that was founded in 1963. The party was led by Nar Bahadur Bhandari. The party supported Sikkim’s merger with India.
• The Sikkim Janata Party was a political party in Sikkim that was founded in 1979. The party was led by Pawan Kumar Chamling. The party supported Sikkim’s autonomy within India.
• The Gorkha National Liberation Front is a political party in the Indian state of West Bengal. The party was founded in 1980 by Subhash Ghisingh. The party campaigns for the rights of the Gorkhas, an ethnic group that is native to the Himalayas.