The correct answer is option 2, Mahatma Gandhi.

Jawaharlal Nehru, as the first Prime Minister of independent India, played a significant role in shaping the country`s policies and providing visionary leadership after its independence. However, Nehru`s contribution to imparting a mass character to the Indian National Congress (INC) was limited.

Subhash Chandra Bose, a prominent leader of the Indian independence movement, played a major role in organizing and leading the Indian National Army (INA) during World War II. Although his efforts were important in the struggle for independence, Bose did not have a direct impact on the mass character of the INC.

Lala Lajpat Rai, also known as Punjab Kesari, was a prominent nationalist leader during the Indian freedom movement. He played a significant role in mobilizing public opinion against British colonial rule. However, he did not specifically impart a mass character to the INC.

The Indian National Congress truly acquired a mass character under the leadership of Mahatma Gandhi. Gandhi`s philosophy and approach, including non-violent civil disobedience and mass mobilization, galvanized millions of Indians to join the struggle for independence. His leadership transformed the INC into a truly mass-based movement, representing the interests and aspirations of a diverse range of