Hint: Wallago Attu is a fast-growing fish. Due to its high nutritional value, it has a good demand as a food fish. It is also popular as a sport fish and has recently entered the ornamental fish market. It was widely distributed; in the past it occurred in India, Bangladesh, Pakistan, Sri Lanka, Nepal, Afghanistan, Indonesia, Myanmar, Thailand, Vietnam and Cambodia.
Elasmobranch: The las (sharks, skates and rays) have hardly developed in hundreds of millions of years, which provides an opportunity to study one of the most basic stages of vertebrate audition evolution. Ears with elastic branches are similar to those in bony fishes and even terrestrial vertebrates. They are also unique among fishes because they have an opening from the inner ear to the surface of the head, called endolymphatic duct.
Resembles shark in body form: The closest relatives of sharks are skates and rays, of which there are more than 600 different species. The other lesser-known relative is the Kameron, which is rare in the ocean today. Sharks, rays, skates and llamas are collectively called cartilaginous fish.
Dangerously predatory: Wallago is a catfish of the Siluridae family and can be found in rivers throughout southern Asia. The Wallago species is a large predatory catfish, so it is called a freshwater shark. There are five rays on their dorsal fin.
Thus the correct answer is option ‘D’.
Note: Freshwater "sharks" are tropical fish with a wide range of length and breadth in the country. This group of people includes barbs, cypresses, mud lo and even goldfish, as well as the "sharks" that we naturally inhabit in the rivers of Asia and Africa.