The correct answer is C. Hyderabad State.
Hyderabad State was a princely state in the Indian subcontinent that existed from 1724 to 1948. It was founded by Nizam-ul-Mulk Asaf Jah I, a Mughal nobleman who was appointed as the viceroy of the Deccan by the Mughal emperor Muhammad Shah. The state was centered on the city of Hyderabad, which was the capital of the Nizams of Hyderabad.
Hyderabad State was one of the largest and most powerful princely states in India. It had a population of over 16 million people and a land area of over 200,000 square kilometers. The state was ruled by the Nizams, who were a Muslim dynasty. The Nizams were known for their wealth and their patronage of the arts.
Hyderabad State was a member of the Indian princely states, which were a group of over 500 independent states that existed in India before independence. The princely states were not part of British India, but they were under British suzerainty. This meant that the British controlled the foreign affairs of the princely states, but the states were otherwise autonomous.
In 1947, India gained independence from British rule. The princely states were given the choice of joining either India or Pakistan. Hyderabad State initially chose to remain independent, but it was eventually annexed by India in 1948.
The other options are incorrect because they were not as large or powerful as Hyderabad State. Gadwal Samsthanam was a small princely state in the Telangana region. Wanaparthy Samsthanam was another small princely state in the Telangana region. Jatprole Samsthanam was a very small princely state in the Telangana region.