6. Researchers gathered a sample of 29 adults from a simple random sample of a list of patients with a chronic medical condition. The distribution of patient ages is given below.

*A graph*

Which test would be the most appropriate to examine the average (mean or median) age in this population?

a. Two-sample t test

b. One-sample t test

c. Wilcoxon rank-sum test

d. Wilcoxon signed rank test