Which of the following is most likely to explain the difference in the regional results?

A governmental auditor was assigned to determine reasons why the students in one region scored significantly higher on education evaluation tests than did the students in another region. Previous research showed that there is a direct correlation between public financial support and student results.

Which of the following is most likely to explain the difference in the regional results?
A . The more successful region spends 30 percent more money on education than does the other region.
B . A higher percentage of the general tax fund is spent on education in the more successful region than in the other region.
C . The more successful region spends more money per student on education than does the other region.
D . The more successful region has increased educational spending by an average of 10 percent each year for the last three years, whereas the other region’s increase averaged only three percent.

Answer: C