In which of the following animals does internal fertilization take place?

A.

Starfish

B.

Fish

C

Frog

D

Cow

The correct answer is option d) Cow.

Frogs and fishes lay eggs which is obviously external fertilization.Starfishes reproduce externally. I heard that starfishes when cut into half, becomes two new individuals. I don't know if it is true.

Hope this helps.