Given H0 (π 1 - π 2) = 0 and H1 (π 1 - π 2) < 0="" where="">π is a percentage, we are testing:
a. A null hypothesis that the percentage in population 1 is smaller than the percentage in population 2
b. A null hypothesis that the percentage population 1 is larger than the percentage population 2
c. A null hypothesis of no difference against an alternative that the percentage of population 1 is smaller than population 2
d. A null hypothesis of no difference against an alternative that the percentage of population 1 is larger than population 2