A cube with 3-inch edges is to be constructed from 27 smaller cubes with 1-inch edges. Twenty-one of the cubes are colored red and 6 are colored white. If the 3 -inch cube is constructed to have the smallest possible white surface area showing, what fraction of the surface area is white?
Answer Choices
A. \dfrac{5}{54}
B. \dfrac{1}{9}
C. \dfrac{5}{27}
D. \dfrac{2}{9}
E. \dfrac{1}{3}