After the Lahore session of the Indian National Congress in December 1929, commitment to "Purna Swaraj" was declared. After that the "Independence day" was observed on:

26 January 1930

The correct answer is Option (2) → 26 January 1930

In the end of December 1929, the Congress held its annual session in the city of Lahore. The meeting was significant for two things: the election of Jawaharlal Nehru as President, signifying the passing of the baton of leadership to the younger generation; and the proclamation of commitment to “Purna Swaraj”, or complete independence. Now the pace of politics picked up once more. On 26 January 1930, “Independence Day” was observed, with the national flag being hoisted in different venues, and patriotic songs being sung. Gandhiji himself issued precise instructions as to how the day should be observed.