Answer:
A. Natural selection
Explanation:
Only the strongest will survive.
We have 20 different amino acids in our bodies.
Answer:
viral envelope
The phospholipids in the viral envelope are similar to those in the plasma membrane of an infected host cell. The viral envelope is, in fact, derived by budding from that membrane, but contains mainly viral glycoproteins.
Answer:
contractile vacuole
Explanation:
contractile vacuole is used for balance of water,salt etc