A principal was buying T-shirts for her school's math club and found that the total cost in dollars could be found by the function f(x) = 12x + 19, where x is the number of
members in the club. If there are at least 9 members on the team but not more than
12, then which of the following statements describes the function?

A. The value of x must be a whole number between 9 and 12 and the value of f(x) must
be a whole number between 127 and 163.

B. The value of x must be a whole number between 9 and 12 and the value of f(x) must
be a whole number between 19 and 12.

C. The value of x must be a whole number between 0 and 163 and the value of f(x)
must be a whole number between 0 and 12.

D. The values of x and f(x) must both be whole numbers between 127 and 163.