A new diet and exercise program claims that it significantly lowers a participant's cholesterol level. In order to test this claim, a sample of 60 participants is taken. Their cholesterol levels are measured before and after the three-month program. Forty of the participants recorded lower cholesterol levels at the end of the program, 18 participants recorded higher cholesterol levels, and 2 participants recorded no change.

a. Using the sign test, specify the competing hypotheses to test the program's claim.

b. Calculate the value of the test statistic.

c. Calculate the p-value.

d. At the 5% significance level, do the data support the program's claim? Explain.