Jim Is Attempting to Develop a Measure That Examines One's

Jim is attempting to develop a measure that examines one's prejudice against people from eastern Europe. Unfortunately, Jim cannot directly measure people's prejudice, so he is inferring people's level of prejudice using a semantic differential scale he's created. What type of variable is Jim measuring?

A) hypothetical variable
B) intervening variable
C) operationalized variable
D) mental measure