C. Surface proteins.
Viral infection begins when proteins on the surface of a virion bind to specific receptor proteins on the surface of host cells.
Explanation:
somebody had helped me when I fell down
(l think not so sure)
Answer: He was capable of being loved.
Explanation: He thought he had to change himself in order to be loved, and felt like he wasn’t enough but he learned his worth.
Just try to make it as imaginable as possible let your readers feel and see what you are writing to them