Hi!
Your answer should be: 3/c, "c= (5)($7)"
Reason being:
A: it only has the number of tickets, so that wouldn't make sense.
B: It has both numbers, but, were not adding, because the tickets cost $7 EACH, so only adding them wouldn't give you the right answer.
C: They are multiplying 5x$7, which is correct because each ticket is $7, and she is trying to buy 5, so 5x$7=c is correct.
D: like A, they only have one part of the problem, so it wouldn't make sense.
Hope this helps!
Yours truly,
~~~PicklePoppers~~~