AMC 10A 2015 Problem 13

Claudia has 12 coins, each of which is a 5 -cent coin or a 10 -cent coin. There are exactly 17 different values that can be obtained as combinations of one or more of her coins. How many 10-cent coins does Claudia have?

Answer Choices
A. 3
B. 4
C. 5
D. 6
E. 7