Question

the class of vertebrate that is said to be extinct and have hinged jaws are
a aves
b amphibia
c osteichthyes
d none of the above

Explanation:

Aves are birds, Amphibia are frogs - like animals, and Osteichthyes are bony - fish, none of which are extinct classes with hinged jaws.

Answer:

D. None of the above