8) A researcher wishes to test whether a particular diet will lower blood pressure. The blood pressure
of 25 randomly selected adults is measured. The median bp reading before the diet period was 145.
After one month on the diet, each person's blood pressure is again measured. For 18 people, the
second blood pressure reading was lower than 145, and for 7 people, the second blood pressure
reading was higher than 145. We would like to use the sign test at the 0.01 significance level to test
the claim that the diet reduces blood pressure. Give the test stat and the p-value for the test.

A) Test statistic: S = 18. P-value: 0.022
B) Test statistic: S = 7. P-value: 0.014
C) Test statistic: S = 18. P-value: 0.007
D) Test statistic: S = 7. P-value: 0.007
E) Test statistic: S = 18. P-value: 0.978