An amusement park sells tickets for adults $15 and tickets for children for $8. We could use the expression 15A for the revenue (money earned) from selling adult tickets on a given day. This being said, what expression could we use to determine the revenue from selling "A" adult tickets and "C" child tickets on a given day?

A. 15A
B. 8C
C. 15A + 8C
D. 15A - 8C