The correct answer is: A. Adivasi Mahasabha
The Adivasi Mahasabha was a political party in India that was founded in 1920. The party was formed to represent the interests of the Adivasi people, who are the indigenous people of India. The Adivasi Mahasabha was the first political party to demand a separate state for the Adivasis, and it played a major role in the creation of the state of Jharkhand in 2000.
The Adivasi Samaj was a social organization that was founded in 1915. The organization was formed to promote the welfare of the Adivasi people. The Adivasi Samaj played a major role in the Adivasi movement, and it was instrumental in the creation of the Adivasi Mahasabha.
The Jharkhand Mukti Morcha is a political party in India that was founded in 1972. The party was formed to demand a separate state for the Adivasis. The Jharkhand Mukti Morcha played a major role in the creation of the state of Jharkhand in 2000.
None of the above is not the correct answer.