SAT Subject Biology Practice Question 384: Answer and Explanation
14. Algae that grows on the shell of a turtle; the turtle is not harmed
C. Interspecific competition
Correct Answer: B
B Because the turtle is not being harmed, eliminate choices that cause harm to one of the parties involved, such as choices A and E. Choice C may not directly cause harm to one of the species involved, but neither are the algae and turtle competing for anything; choice C can be eliminated. Eliminate choice D, because in mutualism both parties must benefit from the association, and while the algae may benefit, the turtle does not.