The "Unsuccessful Mutualists" in Kathleen Keeler's Cost-Benefit Model of Mutualism

Multiple Choice

The "unsuccessful mutualists" in Kathleen Keeler's cost-benefit model of mutualism are those that

A) give benefits to their partner, but fail to receive benefits in return.
B) receive benefits from their partner, but fail to provide benefits in return.
C) neither give benefits to their partner, nor receive them in return.
D) fail to locate individuals of their mutualistic partner effectively.
E) locate mutualistic partners, but fail to overcome their defenses against colonization.