The correct answer is option 1, 1911. The partition of Bengal, which had taken place in 1905, was initially done by the British for administrative purposes. However, it was met with widespread protests and opposition from the Indian nationalist movement. As a result, the British government decided to revoke the partition in 1911. This decision was influenced by the growing unrest in Bengal and the political pressure from Indian leaders such as the Indian National Congress. The revocation of the partition was seen as a victory for the Indian nationalist movement and a significant step towards the unity of Bengal. It is important to note that the partition of Bengal played a significant role in the Indian independence movement and the subsequent events leading to the formation of modern-day India and Bangladesh.