To find out how many students achieved a C average, what process must be followed?

To determine how many students achieved a C average, the most effective process is to calculate the total number of students and then subtract those who have A and B averages. This approach works because it provides a clear pathway to isolate the C averages by eliminating students who fall into the higher academic classifications (A and B). Consequently, by knowing the total number of students and accounting for those with grades above the C average, one can directly ascertain how many students received a C average.

For example, if there are 100 students in total and 30 students achieved A averages while 20 achieved B averages, subtracting those 50 students from the total would give you 50 students who have C averages or lower.

The other choices do not effectively gauge the number of students with a C average. Counting students who did not graduate could include those with all grades—including those below C, hence not providing accurate information. Dividing the class by 4 lacks any meaningful correlation to the average grades and does not account for the different grading distributions. Summing the A and B averages does not lead to the identification of C averages, as it does not delineate between those grades and the C grade category.