The data set below shows the number of books checked out from a library during the first two weeks of the month:

98, 19, 14, 15, 18, 16, 20, 22, 12, 17, 13, 21, 18, 15

which of the following statements is true based on the data set?

a. there is one outlier, indicating very few books were checked out on that day.
b. there are two outliers, indicating very few books were checked out on those two days.
c. there is one outlier, indicating an abnormally large number of books were checked out on that day.
d. there are two outliers, indicating an abnormally large number of books were checked out on those two days.