Which one of the following is the national aquatic animal of India?

The correct answer is C) Gangetic dolphin. The Ministry of Environment and Forests declared the Gangetic dolphin (Platanista gangetica, locally called Susu) the National Aquatic Animal of India in October 2009. It is a freshwater dolphin found in the Ganga-Brahmaputra-Meghna river system and is listed under Schedule I of the Wildlife (Protection) Act, 1972. Its status as a national symbol was reinforced by Project Dolphin, launched in 2020.

• A) Saltwater crocodile: It is a reptile found in coastal and estuarine areas of the Andaman and Nicobar Islands and Odisha, not a national symbol.
• B) Olive ridley turtle: It is a marine sea turtle known for mass nesting at Odisha beaches such as Gahirmatha. It is protected, but it has no national symbol status.
• D) Gharial: It is a critically endangered freshwater crocodilian found in rivers like the Chambal. Conservation work on it is important, but it is not the national aquatic animal.

The core concept here is the list of national symbols, which is a frequent static-GK topic. For Mains, the Gangetic dolphin links well to river pollution, dams and barrages, and the Namami Gange programme, since the dolphin is a bio-indicator of river health.

Trap: Aspirants often pick the gharial or the saltwater crocodile because they are well known and endangered. Remember the national symbol list separately from conservation-status questions.