Question

complete the sentence. animals produce waste, which is used to help the animal grow all stays in the animals body forever their bodies cannot use

Explanation:

The waste produced by animals is the by - product of their metabolic processes. It is not used for growth (as that is what nutrients are for) and does not stay in the body forever (as animals excrete waste). So, it must be something their bodies cannot use.

Answer:

their bodies cannot use