$$\frac{6.75 \times 6.75 \times 6.75 - 4.25 \times 4.25 \times 4.25}{67.5 \times 67.5 + 42.5 \times 42.5 + 67.5 \times 42.5}$$ is equal to:

A

2.5

B

0.25

C

0.0025

D

0.025