An Economist Might Hypothesize That People Will Buy Less Gasoline

An economist might hypothesize that people will buy less gasoline at a price of $1.20 per litre than at $1.00 per litre. In order for the hypothesis to become a theory, it would have to be tested. Which of the following observations would seem to support this hypothesis?

A) Individuals buy less gas because they are purchasing more fuel-efficient vehicles.
B) Gasoline consumption varies with the quantity of cars purchased in each region.
C) Individuals in each region respond to an increase in price by purchasing less gasoline.
D) People in each region buy the same amount of gasoline regardless of the price.