JEE Math Practice Question

Let $$A = \left( {\begin{matrix} 1 & 0 & 0 \\ 2 & 1 & 0 \\ 3 & 2 & 1 \\ \end{matrix} } \right)$$. If $${u_1}$$ and $${u_2}$$ are column matrices such that $$A{u_1} = \left( {\begin{matrix} 1 \\ 0 \\ 0 \\ \end{matrix} } \right)$$ and $$A{u_2} = \left( {\begin{matrix} 0 \\ 1 \\ 0 \\ \end{matrix} } \right),$$ then $${u_1} + {u_2}$$ is equal to :

1. A.$$\left( {\begin{matrix} -1 \\ 1 \\ 0 \\ \end{matrix} } \right)$$
2. B.$$\left( {\begin{matrix} -1 \\ 1 \\ -1 \\ \end{matrix} } \right)$$
3. C.$$\left( {\begin{matrix} -1 \\ -1 \\ 0 \\ \end{matrix} } \right)$$
4. D.$$\left( {\begin{matrix} 1 \\ -1 \\ -1 \\ \end{matrix} } \right)$$