The correct answer is: a) Northern Bihar.
The Valmiki Tiger Reserve is a protected area located in the West Champaran district of Bihar, India. It is the largest tiger reserve in India and the second largest in Asia. The reserve was established in 1973 and covers an area of 3,900 square kilometers. The reserve is home to a variety of wildlife, including tigers, leopards, elephants, rhinoceroses, and deer.
The reserve is named after Valmiki, the author of the Ramayana. Valmiki was born in a village in the area that is now the Valmiki Tiger Reserve. He is considered to be one of the greatest poets in Indian history.
The Valmiki Tiger Reserve is a popular tourist destination. Visitors can go on safaris to see the wildlife, or they can hike in the forests. The reserve is also home to a number of villages, where people live in traditional ways.
The Valmiki Tiger Reserve is an important part of the Indian ecosystem. It is home to a variety of wildlife, and it plays a role in the conservation of tigers. The reserve is also a popular tourist destination, and it helps to support the local economy.
The other options are incorrect because the Valmiki Tiger Reserve is not located in Southern Bihar, Eastern Bihar, or Western Bihar.