There is evidence to support the claim that people become more conservative in their attitudes as they age.Therefore,in an experiment that requires participants to make judgments about the content of music videos,not controlling for the age of participants would be a threat to ______.

A) external validity
B) construct validity
C) internal validity
D) internal reliability

Not controlling for the age of participants would be a threat to internal validity, as age is a potential confounding variable that could affect the relationship between the participants' judgments about the music videos and their levels of conservatism. If the age variable is not controlled, the results may not accurately reflect the true relationship between the two variables being studied (judgments about music videos and conservatism), and alternative explanations for the results (e.g., age-related influences) cannot be ruled out.