Allport chose the term proprium for the

A) master trait that guides life.
B) unconscious forces that motivate behavior.
C) ego or self.
D) superego or conscience.

The main reason for using a 2 × 2 factorial design instead of two separate experiments (with one IV per experiment) is to:

A) find the main effects of each independent variable.
B) find an interaction between the independent variables.
C) save time.
D) manipulate one independent variable at a time.