Which of the following is not a bird?

Answer: A. GOLDEN MAHSEER is NOT a bird — it is a freshwater FISH. (A) Golden Mahseer (Tor putitora): FRESHWATER FISH of the carp family (Cyprinidae). Found in fast-flowing rivers of the Himalayas (Brahmaputra, Ganga and Indus river systems). State fish of Uttarakhand. Listed as Endangered on the IUCN Red List due to habitat loss and overfishing. A famous sport fish. (B) Indian Nightjar (Caprimulgus asiaticus): BIRD. A nocturnal/crepuscular bird with cryptic plumage found across Indian Subcontinent. (C) Spoonbill (Eurasian Spoonbill Platalea leucorodia, Black-faced spoonbill in some regions): BIRD. A wading bird with a distinctive spoon-shaped bill. Found in wetlands across India during winter migration. (D) White Ibis (Black-headed Ibis Threskiornis melanocephalus in India): BIRD. A wading bird of family Threskiornithidae found in wetlands, paddy fields, marshes throughout India. Three of four are wading birds commonly found at Indian wetlands only Golden Mahseer is a fish. Source: BNHS / IUCN Red List / syllabus Biology.