Valmiki National Park is located in West Champaran district of Bihar. It is the largest national park in Bihar and is spread over an area of 899.4 square kilometers. The park is home to a variety of wildlife, including tigers, leopards, elephants, rhinoceroses, and deer. It is also a popular tourist destination.
Option A: Jamui is a district in the Indian state of Bihar. It is located in the south-western part of the state and is bounded by the districts of Munger, Lakhisarai, Banka, and Bhagalpur. The district has a population of over 2.5 million people and its headquarters is the town of Jamui.
Option B: Bhagalpur is a district in the Indian state of Bihar. It is located in the south-eastern part of the state and is bounded by the districts of Banka, Munger, Lakhisarai, and Saharsa. The district has a population of over 4.5 million people and its headquarters is the city of Bhagalpur.
Option C: Buxar is a district in the Indian state of Bihar. It is located in the south-western part of the state and is bounded by the districts of Rohtas, Kaimur, Bhojpur, and Saran. The district has a population of over 2.5 million people and its headquarters is the town of Buxar.
Option D: West Champaran is a district in the Indian state of Bihar. It is located in the north-western part of the state and is bounded by the districts of East Champaran, Sitamarhi, Muzaffarpur, and Darbhanga. The district has a population of over 4.5 million people and its headquarters is the town of Bettiah.
The correct answer is D.