Choose the answer that best represents the situation described below.
Sue wants to mail a glass vase. The bigger the box she uses, the more
packing materials she will need to make sure the vase will not break.
A. The size of the box is a function of the amount of packing
materials needed.
B. The amount of packing materials needed is a function of the size
of the box
C. The size of the box is a function of the size of the vase.