【单选题】Patrick lives near two gas stations, Exxon and Shell. If Exxon decreases the price of gas, we predict that the quantity of gasoline demanded at Shell will
A.
decrease because Exxon and Shell gas are complements.
B.
decrease because Exxon and Shell gas are substitutes.
C.
increase because Exxon and Shell gas are substitutes.
D.
increase because Exxon and Shell gas are complements.
E.
not change Exxon and Shell are different brands of gasoline.