The answer is c because it make the most since if you put in the word in the definition
a. Competition: Humans compete with all organisms for space.
b. Parasitism: Humans have many parasites: head lice, ticks, tapeworms, etc.
c. Mutualism: We have mutualistic relationships with all domesticated plants/animals.
d. Commensalism: Pigeons thrive in metropolitan ecosystems without really
affecting humans (except for being mildly disgusting).
It can be C or D but I think the answer is D
The answer is true, they are only single celled!
C. Medusa. Everything else on the list is a part of another creature, medusa is the only cnidarian here!
