The correct answer is: c) Tawang
Tawang is the largest district of Arunachal Pradesh by area, covering an area of 13,000 square kilometers. It is located in the northwestern part of the state, bordering Bhutan to the north and China to the east. The district is home to the Tawang Monastery, one of the most important Buddhist monasteries in India.
Upper Subansiri is the second largest district in Arunachal Pradesh, covering an area of 10,000 square kilometers. It is located in the northeastern part of the state, bordering Assam to the south and China to the north. The district is home to the Dibang Valley National Park, one of the largest national parks in India.
Changlang is the third largest district in Arunachal Pradesh, covering an area of 8,000 square kilometers. It is located in the southeastern part of the state, bordering Assam to the south and Nagaland to the west. The district is home to the Namdapha National Park, one of the most biodiverse regions in India.
West Kameng is the fourth largest district in Arunachal Pradesh, covering an area of 7,000 square kilometers. It is located in the western part of the state, bordering Bhutan to the north and Assam to the south. The district is home to the Kameng National Park, one of the most popular tourist destinations in Arunachal Pradesh.