An Advantage of the Case Study Method Is That It

An advantage of the case study method is that it , whereas a disadvantage of the case study method is that it _.

A) eliminates researcher bias; has high participant bias
B) allows an in-depth study of rare phenomenon; has poor generalizability
C) can be used to determine cause-and-effect relationships; has low internal validity
D) has high internal validity; is costly to run
E) None of these choices are correct.