Which of the following groups is MOST likely to have been used as subjects for psychological research?

A) a variety of individuals
B) lower-class males
C) lower-class males and females
D) middle- and upper-class white males

Historically, psychology research has primarily used middle- and upper-class white males as study participants. This is due to various factors such as accessibility and convenience, as well as the biases and preferences of researchers. However, in recent years, there has been a greater emphasis on studying diverse populations and incorporating intersectionality into research design.