The correct answer is (c) 1956.
Andhra Pradesh was created as a linguistic state on November 1, 1956, by merging the Telugu-speaking areas of the erstwhile Hyderabad State, Madras State, and Mysore State. The state was named after the Telugu-speaking region of Andhra, which is located in the south-central part of India.
The creation of Andhra Pradesh was a major milestone in the history of Indian federalism. It was the first state to be created on the basis of language, and it set a precedent for the creation of other linguistic states in India. The creation of Andhra Pradesh also led to the development of a strong sense of Telugu identity among the people of the state.
The options (a), (b), and (d) are incorrect because Andhra Pradesh was not created as a linguistic state in those years.