Calculate the volume of each box:

• Box A: $4 \times 4 \times 3 = 48$ cubic inches
• Box B: $3 \times 3 \times 4 = 36$ cubic inches
• Box C: $4 \times 3 \times 1 = 12$ cubic inches

The difference between Box A and Box B:

$48 - 36 = 12 \text{ cubic inches}$

Since Box C has a volume of 12 cubic inches:

$\frac{48 - 36}{12} = \frac{12}{12} = 1$

The difference equals exactly 1 Box C.