Which characteristics are common to amphibians, lemurs, and humans?

vertebrae, tetrapod, hair

amniotic egg, hair, biped

tetrapod, vertebrae

tetrapod, hair

A small, lemur-like creature may have been an early ancestor of monkeys, apes, and humans.

Let's see what these words mean:

Vertebrae means a backbone as well as an internal skeleton

Hair is the body's way of creating a defense for the skin (and additionally to look bigger)

Tetrapod is a four footed animal

Amniotic egg means that the embryo develops inside an egg.

Biped means using two feet to walk.

Amphibians, lemurs, and humans both have vertebrae and tetrapod. While humans do not walk on four legs it is said that humans are classified as that group