Correct option is B
Sikkim became the 22nd state of India on 16th May 1975. Before this, Sikkim was a protectorate under Indian suzerainty, with its monarchy in place. The political transition began after a referendum in which the people of Sikkim overwhelmingly voted in favor of abolishing the monarchy and integrating with India. The then Prime Minister of Sikkim, Kazi Lhendup Dorjee, played a crucial role in this process.
Following the integration, the Indian Parliament passed the 36th Amendment Act, which made Sikkim a full-fledged state of the Indian Union. Sikkim's accession to India is considered one of the more peaceful and successful political integrations in the country’s post-independence history.
