Answer:
Correct option: A. Weight.
Step-by-step explanation:
In regression analysis there are two kinds of variables: Explanatory and Response variable.
The explanatory variable are used to predict the changes in the response variable. They are also known as independent or predictor variable.
The response variable are observed for any changes caused by the explanatory variable. They are also known as the dependent or experimental variable.
In this case it is provided that heavier cars have lower fuel efficiencies.
It implies that there is linear inverse relationship between the variables weight of the car and fuel efficiency.
The response variable is the fuel efficiency and the explanatory variable is the weight of the car. Since the weight of the car is used to determine the fuel efficiency.
Thus, the explanatory variable is the weight of the car.
