A psychology class has been assigned an individual case study project as well as a group project. The members of the group will receive the same grade for the group project, but they will be graded separately for their individual projects. Kari, Mihail, Sherifa, and Siti are members of one such group. Kari and Sherifa worked very hard on the group project. Mihail and Siti, however, did not contribute much to the group project because they felt that Kari and Sherifa would manage to get good grades for it. Instead, they focused their efforts on their individual projects. Which of the following answer options best exemplifies Mihail and Sitis behavior?

A. motivational loss

B. coordination loss

C. production blocking

D. social loafing

E. synergy