Bihar is the 13th largest state in India by area, covering an area of 94,163 square kilometers (36,357 sq mi). It is bordered by Nepal to the north, the Indian states of Uttar Pradesh to the west, Jharkhand to the south, West Bengal to the east, and the Bay of Bengal to the southeast.
The correct answer is: 13.
Option A: 12 is incorrect. Bihar is larger than the state of Manipur, which is the 12th largest state in India by area.
Option B: 10 is incorrect. Bihar is larger than the state of Meghalaya, which is the 10th largest state in India by area.
Option C: 13 is correct. Bihar is the 13th largest state in India by area.
Option D: 11 is incorrect. Bihar is larger than the state of Tripura, which is the 11th largest state in India by area.