15. In the figure 2 composed of numbers and letters, there are ( ) different paths to spell out AMC8. Requirement: Each path starts from the letter A in the middle of the figure, and allows passing through adjacent letters or numbers once (can move up, down, left, or right, but not diagonally). For example, figure 2 marks one path that meets the condition.
(A) 8
(B) 9
(C) 12
(D) 24
\begin{tabular}{|c|c|c|c|c|}
\cline { 2 - 4 } \multicolumn{1}{r|}{} & 8 & $\mathrm{C}$ & 8 & \multicolumn{1}{|c}{} \\
\hline 8 & $\mathrm{C}$ & $\mathrm{M}$ & $\mathrm{C}$ & 8 \\
\hline $\mathrm{C}$ & $\mathrm{M}$ & $\mathrm{A}$ & $\mathrm{M}$ & $\mathrm{C}$ \\
\hline 8 & $\mathrm{C}$ & $\mathrm{M}$ & $\mathrm{C}$ & 8 \\
\hline & 8 & $\mathrm{C}$ & 8 & \multicolumn{1}{|c}{} \\
\cline { 2 - 4 } & & &
\end{tabular}
(E) 36
Figure 2
15. D.

By the multiplication principle, we know that the desired result is
$$
1 \times 4 \times 3 \times 2=24 \text {. }
$$