A student has a data file containing 10,000 numerical values. The student is writing a program to compute the average of the numbers contained in the file. Which of the following procedures is most likely to be useful in the student's program?
a. A procedure that returns the quotient when dividing one value by another
b. A procedure that returns the sum when adding one value to another
c. A procedure that returns the sum of the values in the file
d. A procedure that returns true if the file contains any duplicate values and returns false otherwise