A Group of Participants Is Given a Hammer

A group of participants is given a hammer.They are asked to collectively strike the hammer onto a pad as hard as possible.Under which of the following circumstances would people try less hard on this group task than if they performed it individually?

A) They do not have relationships with the other group members.
B) They are all women.
C) They are from a collectivistic culture.
D) Their individual contributions are monitored.
E) They did not have a sufficiently filling meal prior to the task.