The correct answer is C. Uttar Pradesh.
Gorakhpur is a city in the Indian state of Uttar Pradesh. It is the headquarters of Gorakhpur district and Gorakhpur division. The city is located on the banks of the Rapti River, about 272 kilometers (170 mi) east of the state capital, Lucknow. Gorakhpur is a major railway junction and is well-connected to other parts of India by road and rail. The city is also home to Gorakhnath Temple, one of the most important Hindu temples in India.
The longest railway platform in the world is located at Gorakhpur railway station. The platform is 1,366 meters (4,481 ft) long and can accommodate 24 trains at a time. The platform was built in 1926 and is used by the Indian Railways to handle the large number of passengers who travel to and from Gorakhpur.
The other options are incorrect. Odisha is a state in eastern India. West Bengal is a state in eastern India. Chhattisgarh is a state in central India.