The correct answer is option 'A' - Kolkata.

Explanation:
Kolkata, formerly known as Calcutta, was the capital of India during the British colonial rule, from 1772 until 1911. The British East India Company established Kolkata as their headquarters in the early 18th century and it soon became an important center for trade and administration.

During the early years of British rule in India, the capital of the British territories was initially located in Chennai (then known as Madras). However, due to security concerns and the need for a more central location, the capital was shifted to Kolkata in 1772.

Kolkata remained the capital of British India for almost 140 years. It was during this period that the city witnessed significant development and became a major center of culture, education, and politics.

However, in 1911, the capital was shifted from Kolkata to Delhi. The main reason for this shift was the growing nationalist movement in India, which demanded the capital to be located in a more Indian-centric city. Kolkata, being the center of British power and administration, was seen as a symbol of colonial rule.

The decision to shift the capital to Delhi was also influenced by the strategic location of the city, as it was more centrally located and had better access to other parts of the country. Additionally, Delhi had historical significance as it had been the capital of various Indian dynasties in the past.

After independence in 1947, Delhi continued to be the capital of India, and Kolkata became the capital of the state of West Bengal. Despite losing its status as the national capital, Kolkata remains an important cultural, educational, and commercial center in India.

In conclusion, Kolkata was the capital of India during the British colonial rule, but it was later shifted to Delhi in 1911.