14. The surface area of a rectangular box is 94 square inches, and the sum of the lengths of all its edges is 48 inches. Then the sum of the lengths of all its body diagonals is $(\quad)$.
(A) $8 \sqrt{3}$
(B) $10 \sqrt{2}$
(C) $16 \sqrt{3}$
(D) $20 \sqrt{2}$
(E) $40 \sqrt{2}$
14. D.

Let the length, width, and height of the box be $x$, $y$, and $z$ respectively. Then $2(xy + yz + zx) = 94$, $4(x + y + z) = 48$.
$$
\begin{array}{l}
\text { Hence } x^{2} + y^{2} + z^{2} \\
= (x + y + z)^{2} - 2(xy + yz + zx) \\
= 12^{2} - 94 = 50 \text {. }
\end{array}
$$

Therefore, the sum of the lengths of all the body diagonals of the box is
$$
4 \sqrt{x^{2} + y^{2} + z^{2}} = 20 \sqrt{2} \text {. }
$$