Neither whales nor pythons have hind legs, but both have internal remnants of legs and hip bones. snakes and whales must have

The correct answer is: common ancestor

Explanation:

Hello! Let's solve this!

According to the evolution of living beings, we all have an ancestor.

Depending on the branch in which the living being is, it unites with the ancestor of another.

Two different branches that never join, do not have a common ancestor. In this case, they have a characteristic that unites them, so whales and pythons have a common ancestor.

The correct answer is: common ancestor

i think the answer is

mass