Question

Which of the following is not a true fish?
A) shark
B) eel
C) starfish
D) seahorse

Answer 1

I think the answer is   (a) shark


but I'm, not soo sure about the answer 
   hope it helps you

Answer 2

Answer:C starfish

Explanation: starfish belongs to kingdom echinodermata and all three can swim except starfish

I hope

This will clear your doubt