Why are only inherited traits, not acquired ones, necessary for the process of natural selection?

(there is no science category so i just chose biology) need the diagram below shows a cell placed in a solution. only water is allowed to move in and out of the cell. what will most likely happen to the cell? it will expand as water moves out of it. it will shrink as water moves out of it. it will expand as water moves into it. it will shrink as water moves into it.