The correct answer is (c). Mahatma Gandhi attended the Third Round Table Conference held in London in 1932.
The First Round Table Conference was held in London in 1930. It was attended by representatives of the British government, the Indian National Congress, and other Indian political parties. The conference failed to reach an agreement on the future of India.
The Second Round Table Conference was held in London in 1931. It was attended by the same representatives as the First Round Table Conference, but it also included representatives of the princely states. The conference failed to reach an agreement on the future of India.
The Third Round Table Conference was held in London in 1932. It was attended by the same representatives as the Second Round Table Conference, but it also included representatives of the Muslim League. The conference reached an agreement on the future of India, which was later implemented in the Government of India Act of 1935.
Mahatma Gandhi was not present at the First Round Table Conference because he was boycotting the British government. He was also not present at the Second Round Table Conference because he was in jail. However, he was present at the Third Round Table Conference, where he played a key role in the negotiations.