Which of the following hypotheses would need a one-tailed test?

A、Hybrid cars get better gas mileage than traditional cars.
B、There is a difference in the gas mileage of cars and trucks.
C、There is no difference in gas mileage among two-door and four-door vehicles.
D、There is a relationship between the number of miles to one's job and the gas mileage associated with his or her chosen car.
E、All of the above would need a one-tailed test.