In the diagram, the numbers $1,2,4,5,6$, and 8 are substituted, in some order, for the letters $A, B, C, D, E$, and $F$, so that the number

$\begin{array}{llll}A & 10 & B & C\end{array}$ between and below two numbers is the positive difference between those two numbers. For example, the 7 in the third row is the D $9 \quad E$ $7 \quad F$

3 positive difference between $D$ and 9 . Thus $D=2$ because $9-2=7$. The value of $A+C$ is
(A) 7
(B) 12
(C) 13
(D) 10
(E) 14