Research on Social Facilitation Warrants Some Practical Advice

Research on social facilitation warrants some practical advice.All of the following recommendations are supported by this research except for one.Which one?

A) When students want to memorize unfamiliar information, they should do it alone.
B) When students want to review material they have already learned, they should not do it in a study group.
C) When supervisors want their employees to do simple tasks well, they should have the employees do them in the presence of others.
D) When supervisors want their employees to complete challenging tasks, they should give employees some privacy.