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).
Answer:
I'm sorry. I wanted to try and answer the question but I can't because it isn't clear.
I think that the correct answer to this question is D .
I am making a educated guess and saying producers. Plants mostly.
