【正确答案】 E

【答案解析】You are given that the product of the average of a list of course grades and the total number of courses is n. Recall that average, A, is equal to the sum of the course grades, G, divided by the number of courses, C; thus [*]. Because n is the product of the number of courses, C, and the average of the course grades, A, n=AC. Further, because [*], multiplying both sides by C yields G=AC. Finally because n=AC and G=AC, it follows that n=G. Thus n is the sum of the course grades.