All of the following are cartilaginous fish except the
a. manta ray.
b. whale shark.
c. great white shark.
d. iridescent shark catfish.

The answer is (d.) iridescent shark catfish.

Cartilaginous fishes are vertebrates that has jaws, paired fins, scales, and a heart like whale shark, great white shark, and manta ray. This class of fishes are divided into two: Elasmobranchii and Holocephali. While iridescent shark catfish is simply a shark catfish but not a shark.

A. radioactive dating