In a Study to Investigate the Effect of Regular Exercise

Multiple Choice

In a study to investigate the effect of regular exercise on raising HDL (good cholesterol) levels, a random sample of five male subjects known to have low HDL levels had their HDL measured. After six months on a regular exercise schedule, it was measured again. The data are given in the following table. How do you know that the data should be analyzed using the Wilcoxon signed rank test?

A) There are three groups, and some of the observations are negative numbers.
B) There are three groups, with one observation in each group matched to a subject.
C) There are two groups, and some of the observations are negative numbers.
D) There are two groups, with one observation in each group matched to a subject.