A Paint Manufacturer Fills Cans of Paint Using a Machine

Multiple Choice

A paint manufacturer fills cans of paint using a machine that has been calibrated to fill the cans to contain an average  of 1 gallon (128 ounces) each. To test whether their machine has come out of calibration, the manufacturer takes a random sample of 25 cans and finds that they average 128.2 ounces with a standard deviation of 2 ounces. Is this strong evidence that the filling machine is set too high and thus is no longer calibrated properly?
What are the null and alternative hypotheses in this situation?

A) H₀:  = 128 H_a:  < 128
B) H₀:  = 128 H_a:  > 128
C) H₀:  = 128 H_a:   128
D) H₀:  = 128 H_a:  = 128.2