Which of the following is a cartilaginous fish?

Correct option is A

Sol. Sharks belong to the group of cartilaginous fish.
 Cartilaginous fish are characterized by having skeletons made of cartilage rather than bone. This group also includes rays and skates.
 Cartilaginous fishes are fearsome predators and harmless mollusc-eaters belonging to the class Chondrichthyes.
 They are cold-blooded (poikilotherms) animals.
 Cartilaginous fishes are ureotelic as they excrete nitrogenous waste in the form of urea.
 In contrast, bony fish, such as rohu, salmon, and tuna, have skeletons made of bone.