Answer :
Using variable concepts, it is found that the explanatory variable is the age.
Explanatory and response variables:
- The variables of an experiment are divided into explanatory and response.
- The response variable is the one that is the focus of the study, that is, the one that can be changed.
- The explanatory is the one that explains the reason of the change in the response variable.
In this problem, the age can effect the political party preference, hence:
- The variable that is changed is the political party preference, hence it is the response variable.
- The reason is the age, hence it is the explanatory variable.
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