Question

what kind of fish are the sharks?
select one:
a. chondrichthyes
b. osteichthyes
c. agnatha

what fin is used by fish to propel itself forward?
select one:
a. he uses his pelvic fins to swim
b. he uses his caudal fin to swim
c. he uses his pectoral fins to swim

Explanation:

For the first question: Sharks belong to the class Chondrichthyes, which are cartilaginous fish with skeletons made of cartilage instead of bone. Osteichthyes are bony fish, and Agnatha are jawless fish, neither of which describe sharks.
For the second question: The caudal (tail) fin is the primary fin fish use to generate thrust and propel themselves forward. Pelvic and pectoral fins are mainly for balance, steering, and stopping.

Answer:

1. a. Chondrichthyes
2. b. He uses his caudal fin to swim