Correct Answer: (c) 4, 3, 2, 1
Solution:Gandhi-Irwin Pact: Congress authorized Gandhi to negotiate with the Viceroy. After a long conversation between Gandhi and Lord Irwin, a pact known as Gandhi-Irwin Pact was signed on March 5, 1931.
Execution of Bhagat Singh: Bhagat Singh, Rajguru, and Sukhdev were hanged on March 23, 1931.
Karachi Session of Congress: Congress confirmed the Gandhi-Irwin Pact in the annual session at Karachi held on March 29-31, 1931.
Second Round Table Conference: The second session of the Round Table Conference started on September 7, 1931 in which Mahatma Gandhi attended the Conference as the sole representative of Congress. This Conference was a complete failure.