$A$ larval stage occurs in the life history of all members of the group:

Give an example of the following:
$(a)$ Roundworm
$(b)$ Fish possessing poison sting
$(c)$ $A$ limbless reptile/amphibian
$(d)$ An oviparous mammal

Which of the following is unrelated to the others?

Which of the following is $NOT$ true for $Phylum$ $Echinodermata$?

Which of the following characteristics are $NOT$ common to both Aves (birds) and Mammalia (mammals)?
$I$ - Homeothermic (warm-blooded) animals.
$II$ - Respire through lungs.
$III$ - Possess a four-chambered heart.
$IV$ - Dioecious (sexes are separate).
$V$ - Possess hair on the skin.
$VI$ - Show internal fertilization.
$VII$ - Possess teeth.

Identify the incorrect matching.