Answer:
A. Protein Spikes
Explanation:
A viruses are defined as the quintessential parasites in the living world. They are a chain of the nucleic acids that lives in a host cell. Without the host cell, all the viruses cannot carry out their life sustaining activities or functions. They are always housed in a protein layer or a protein coat. All the viruses contains the RNA or the DNA. The protein spikes which is on the outside of a virus are "sticky" and they are attracted to the specific molecules of the outside of an animal cells.
