Sydney wants to find the best deal for Charlie. Petco sells a pack of 12 cans of dog food for $15.00. Petsmart sells a pack of 20 cans for dog food for $23.00. Costco sells dog cans in large quantities, 45 cans for $50. Which store has the best deal?
A. Petco
B. Petsmart
C. Costco