Jaws First Occurred in Which Extant Group of Fishes

Question

Jaws first occurred in which extant group of fishes?
A)lampreys
B)chondrichthyans
C)ray-finned fishes
D)lungfishes
E)placoderms

Accepted Answer

Jaws are a characteristic feature of chondrichthyans (cartilaginous fishes) such as sharks, rays, and chimaeras. Lampreys, ray-finned fishes, lungfishes, and placoderms do not have true jaws.