I think the answer is "viruses can only multiply within a living cell." the other ones don't really sound right. but i'm not absolutely sure.
1)Enzyme is a protein. The main material of an enzyme is protein
2)It is easily influenced, by environmental change. Environmental factors include temperature, pH, and inhibitor.
3)It acts as catalyst The enzyme functions in accelerating chemical reaction, but the enzyme itself does not change after the reaction ends.
The reason I said that you are wrong is because no
