Please help! will give brainliest :))

A, D, B

Explanation:

All have layers protecting the inside.

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.

a scenario where a cell may be needed to perform a form of endocytosis is when transporting large molecules. a scenario where a cell may be needed to perform a form of exocytosis is when releasing the large molecule from the cell.