The correct option is A Valmiki National Park
Valmiki National Park, Tiger Reserve and Wildlife Sanctuary are located at the India-Nepal border in the West Champaran district of Bihar, India on the bank of river Gandak. It is the only National park in Bihar. The extensive forest area of Valmikinagar was previously owned by the Bettiah Raj and Ramanagar Raj until the early 1950s. Valmiki Tiger Reserve (VTR) is one of the natural virgin recesses in east India, situated in the northwest corner of Bihar. The pristine forest and wilderness of VTR is an excellent example of a Himalayan Terai landscape. VTR comprises the Valmiki National Park and Valmiki Wildlife Sanctuary. The VTR forest area covers 899.38 square kilometers (347.25 sq mi), which is 17.4% of the total geographical area of the district West Champaran. As of 2018, there were 40 tigers in the Reserve.