What is an example of parasitism?

Question

Is it:

a) The relationship between the marine annelid Chaetopterus and tiny crabs of the genus Pinnixa

b) Rabbits infected with myxoma virus

c) Cleaner fish

d) All of the above.

Please, help me.. I do not understand this.

I know that I don't think it's A.

Answer 1

I would say B because the virus is eating off the rabbit.

Answer 2

The rabbits.  Parasitism is related to get advantage from another living thing, but not cooperating, just taking advantage even causing problems to it.