When the hypotheses H 0 : 100 and H a : < 100 are

When the hypotheses H ₀ : µ ≥ 100 and H _a : µ < 100 are being tested at a level of significance of α, the null hypothesis will be rejected if the test statistic z is

a. > z _α

b. > -z _α

c. < -z _α

d. < 100