The correct answer is option 2, Jawaharlal Nehru.

In 1946, an Interim Cabinet was formed in India to assist with the transition of India to an independent nation. This was before the official independence in 1947. Jawaharlal Nehru, who later became the first Prime Minister of independent India, was the head of this Interim Cabinet.

Option 1, Rajendra Prasad, is incorrect. Though Rajendra Prasad was an instrumental figure in Indian freedom fight and became the first President of India, he did not head the Interim Cabinet.

Option 3, Sardar Vallabhbhai Patel, is also incorrect. He was a key member of the cabinet and later became the first deputy prime minister and first minister of home affairs of India, but he did not head the Interim Cabinet.

Option 4, Rajagopalachari, is incorrect too. He served as the last Governor General of India, also not the head of the Interim Cabinet.