Which of the following National Parks is unique in being a swamp with

Which of the following National Parks is unique in being a swamp with floating vegetation that supports a rich biodiversity?

Bhitarkanika National Park
Keibul Lamjao National Park
Keoladeo Ghana National Park
Sultanpur National Park
This question was previously asked in
UPSC IAS – 2015
Keibul Lamjao National Park is unique in being a swamp with floating vegetation that supports a rich biodiversity.
Keibul Lamjao National Park, located in Manipur, is the only floating national park in the world. It is situated on Loktak Lake and is characterised by unique floating islands called ‘phumdis’, which are heterogeneous masses of vegetation, soil, and organic matter at various stages of decomposition. This habitat is home to the critically endangered Sangai (Manipur brow-antlered deer), also known as the dancing deer.
Bhitarkanika National Park (Odisha) is known for its mangrove ecosystem and salt-water crocodiles. Keoladeo Ghana National Park (Rajasthan) is a famous wetland bird sanctuary. Sultanpur National Park (Haryana) is also a significant bird sanctuary. None of these are characterised by extensive floating vegetation (phumdis) in the manner of Keibul Lamjao.