Correct Option
The correct option is 2 - 4 - 1 - 3.
Explanation
The period from 1929 to 1931 represents a decisive phase in the Indian National Movement, transitioning from the demand for Dominion Status to Complete Independence (Purna Swaraj), followed by the Civil Disobedience Movement and subsequent negotiations with the British Government.
The Lahore Session of the Indian National Congress was held in December 1929 under the presidency of Jawaharlal Nehru. This session is historically significant for passing the 'Purna Swaraj' (Complete Independence) resolution. Consequently, January 26, 1930, was observed as the first Independence Day across India.
The Gandhi-Irwin Pact was signed on March 5, 1931, not in 1929. This agreement between Mahatma Gandhi and Viceroy Lord Irwin led to the suspension of the Civil Disobedience Movement and the Congress agreeing to participate in the Second Round Table Conference.
The Second Round Table Conference (held in London from September to December 1931) did not result in immediate independence. The conference failed to yield substantial constitutional progress, largely due to a deadlock on the communal question and minority representation. Mahatma Gandhi returned to India without success, leading to the resumption of the Civil Disobedience Movement.
Key Takeaway: The correct chronological sequence of these events is: Lahore Session (Dec 1929) $\rightarrow$ Civil Disobedience Movement (1930) $\rightarrow$ Gandhi-Irwin Pact (March 1931) $\rightarrow$ Second Round Table Conference (Late 1931).