The correct answer is option 1, elephants. Manas Sanctuary in Assam is known for its elephant population. Manas Sanctuary is a wildlife sanctuary located in the foothills of the Eastern Himalayas and is a part of the UNESCO World Heritage Site. The sanctuary is home to a diverse range of wildlife, including a large number of elephants. The sanctuary provides a suitable habitat for elephants due to its rich biodiversity and vast vegetation cover which provides them with ample food and water sources. The elephant population in Manas Sanctuary plays a crucial role in maintaining the ecological balance of the region. They are also a major attraction for tourists and wildlife enthusiasts visiting the sanctuary.