Find the Indicated Sum or Difference, If It Is Defined

Multiple Choice

Find the indicated sum or difference, if it is defined.
- $$\left[ \begin{array} { l l } - 1 & - 6 \\- 1 & - 8 \\- 6 & - 5\end{array} \right] + \left[ \begin{array} { r r } 6 & 3 \\- 2 & - 2 \\- 5 & - 6\end{array} \right]$$

A) $\left[ \begin{array} { r r } 5 & - 3 \\ - 3 & - 10 \\ - 11 & - 11 \end{array} \right]$
B) $\left[ \begin{array} { r r } - 7 & - 9 \\ 1 & - 6 \\ - 1 & - 12 \end{array} \right]$
C) $\left[ \begin{array} { r r } 5 & - 8 \\ - 3 & - 10 \\ - 11 & - 11 \end{array} \right]$
D) not defined