Dr. mccall found that class projects were of poorer quality when students worked in groups compared to when each student did an individual project. this difference can be explained by the phenomenon of:
a. cognitive dissonance
b. social loafing
c. the sleeper effect
d. polarization

b. social loafing

Explanation:

In sociology, the term social loafing refers to the phenomenon by which  people tend to exert less effort on a task if they are in a group versus when they work alone. In other words, when people are working in a group they exert less effort and therefore the results can be poorer than when working by themselves.

In this example, Dr. McCall found that class projects were of poorer quality when students worked in groups compared to when they did individual projects. We can see that the students might be exerting less effort on the class projects and therefore they are getting poorer results. Therefore, this would be an example of social loafing.

answer; i believe its called ; checks   and balances;