#### Answer

The operation is not defined.

#### Work Step by Step

Here we need to find $ B+C $. Therefore consider, $ B+C=\left[ \begin{array}{*{35}{l}}
0 & -2 \\
3 & 2 \\
1 & -5 \\
\end{array} \right]+\left[ \begin{matrix}
1 & 2 & 3 \\
-1 & 1 & 2 \\
-1 & 2 & 1 \\
\end{matrix} \right]$
This operation is not defined since only two matrices of the same order can be added; here, the size of matrix B is $3\times 2$ and the size of the matrix $ C $ is $3\times 3$, so addition is not possible. Thus, the operation is not defined.