Which of the Following Features is Shared by All Animals

Question

Which of the following features is shared by all animals?
A) an external body surface that is dry
B) a basic body plan that resembles a two-layered sac
C) a body surface covered with hair to keep them warm
D) contact between their cells and an aqueous medium

Accepted Answer

All animals have cells that must exchange nutrients and waste with their environment, necessitating contact between their cells and an aqueous (water-based) medium. This is a fundamental requirement for animal life, unlike the other options which are not shared by all animals.