设二维随机变量(X,Y)的分布律为 & (0) & (1) & (2) X 0 & (1)/(12) & (2)/(12) & (2)/(12) 1 & (1)/(12) & (1)/(12) & 0 2 & (2)/(12) & (1)/(12) & (2)/(12) =().A. (3)/(12)B. (2)/(12)C. (4)/(12)D. (1)/(12)

设二维随机变量$(X,Y)$的分布律为$\begin{array}{c|c|c|c} & {0} & {1} & {2} \\ \hline X \\ \hline 0 & \frac{1}{12} & \frac{2}{12} & \frac{2}{12} \\ \hline 1 & \frac{1}{12} & \frac{1}{12} & 0 \\ \hline 2 & \frac{2}{12} & \frac{1}{12} & \frac{2}{12} \end{array}$，则$P\{X+Y=1\}=$().

A. $\frac{3}{12}$

B. $\frac{2}{12}$

C. $\frac{4}{12}$

D. $\frac{1}{12}$