Aspecies of insect is newly introduced into the united states from the philippines. this insect becomes established, laying its eggs on the leaves of oak trees. how can a biologist determine if the relationship between the insect and the oak tree is commensalism, mutualism, or parasitism?
a) if the insect benefits, the relationship is parasitism.
b) if both the insect and the tree benefit, the relationship is commensalism.
c) if the insect benefits and the tree neither benefits nor is harmed, the relationship is mutualism.
d) if the insect benefits and the tree neither benefits nor is harmed, the relationship is commensalism.

If the insect benefits and the tree neither benefits nor is harmed, the relationship is commensalism.

In commensalism, one organism, the commensal, benefits, and the other organism, the host, is apparently unaffected. Since the insect is gaining benefit and tree is neither harmed nor affected, this relationship can be investigated to be commensalism.

stimulus is a change in the environment that causes an organism to react. the response is the reaction to the stimulus. some examples of stimuli for zebras are drought, to many predators, and bad feeding grounds such as dead grass or plants. zebras respond to stimuli just like all other living organisms

i would think a oil tanker that has leaked in a bay