The capital city of Sikkim is:

The correct answer is: a) Gangtok.

Gangtok is the capital of the Indian state of Sikkim. It is located in the eastern Himalayas, at an elevation of 2,205 meters (7,234 feet). The city has a population of about 100,000 people.

Gangtok is a popular tourist destination, known for its beautiful scenery, temples, and monasteries. The city is also home to the Sikkim government and several educational institutions.

Here is a brief description of each option:

• a) Gangtok: The capital of Sikkim, located in the eastern Himalayas.
• b) Namchi: A town in the Indian state of Sikkim, located about 50 kilometers (31 miles) from Gangtok.
• c) Pelling: A town in the Indian state of Sikkim, located about 125 kilometers (78 miles) from Gangtok.
• d) Ravangla: A town in the Indian state of Sikkim, located about 150 kilometers (93 miles) from Gangtok.