Explanation:

About Gorumara National Park

• It is located in the Eastern Himalayas’ submontane Terai belt.
• This region has rolling forests and riverine grasslands, and is known as the Dooars in West Bengal.
• The park is located on the flood plains of the Murti River and Raidak River. The major river of the park is the Jaldhaka river, a tributary of the Brahmaputra river system.
• In this regard, Gorumara is a significant watershed area between the Ganges and Brahmaputra river systems.
• The park is rich in large herbivores including Indian rhinoceros, gaur, Asian elephant, sloth bear, chital, and sambar deer. Small herbivores include barking deer, hog deer and wild boar.

Hence only statements 2&3 are correct.