Byproduct Mutualism (BM) Differs from Reciprocity (REC) in Which of the Following

Byproduct mutualism (BM) differs from reciprocity (REC) in which of the following ways?

A) Scorekeeping is not required in BM or REC, but there is a temptation to cheat in REC.
B) In REC, but not BM, there is no temptation to cheat, nor do individuals have to keep track of their partner's behavior.
C) In BM, but not REC, there is no temptation to cheat, nor do individuals have to keep track of their partner's behavior.
D) There is no temptation to cheat in BM or REC, but scorekeeping is required in REC.
E) There is no temptation to cheat in BM or REC, but scorekeeping is required in BM.