Answer:
D
Explanation:
If the price of gasoline increases, it would become more expensive to own a car. As a result, the demand for new cars would fall.
public transportation can be regarded as a substitute for new cars, if public transportation becomes cheaper, the demand for new cars would fall.
Taking these two occurrences together, the demand curve for cars would shift leftward. Equilibrium price and quantity would fall.
If the price of steel to produce cars decreases, it would become cheaper to make cars. Thus, the supply of cars would increase. the supply curve would shift rightward and the equilibrium price would reduce while quantity would increase.
Taking these three occurrences together, equilibrium price would fall while the effect on quantity is ambiguous
