Over the past six years, most of the students in Tupac city have

The right answer is C. Since this question is asking us to support the conclusion, we must first ID that conclusion. In this case it is that "colleges in Tupac city ([i]represent!) will see a surge in the number of students enrolling with them to pursue their graduate degrees[/i]". The main premise that this is based on is that Mekon city is going to increase tuition, and a lot of Tupac-ians go to Mekon for university.
Hence, an assumption that this argument is based on would have to connect tuition price in Mekon to choosing where to study.

A - If anything, this would not support the conclusion. OUT

B - Once again, if true this does not support the conclusion. OUT

C - If the low price in Mekon is the reason for students going there, then indeed, the premise and the conclusion are linked correctly. CORRECT

D - If this is the case, then why would changing the fees have any impact. Irrelevant and OUT.

E - The number of colleges is not linked to choosing to enroll at a place. The only oblique relationship is that this may impact tuition fees, but we already see that treated as a separate concept, so this would require a further assumption on our part. OUT

- Matoo