Social loafing is most likely to occur among a. audience members who are asked to applaud after a speaker is introduced b. factory workers paid on the basis of individual level of productivity c. a group of runners competing for first place in a race d. students who are each assigned a different topic for their course term papers

I believe the answer is: a.  audience members who are asked to applaud after a speaker is introduced.

Social loafing refers to the social process when an individuals start to making less effort to work when they're in a group setting compared to when they're working individually.
When audiences is asked to give applaud , most of you would notice that some of the audiences would clap slower or not clap at all because they believe the other audiences would cover for them.

United states v.  nixon, 418  u.s.  683 (1974),  was  a landmark  united states supreme court case  that resulted in a unanimous  decision  against president richard  nixon, ordering him to deliver tape recordings  and  other subpoenaed materials to a  federal  district  court.