Use the Two-Stage Method to Solve $x_{1} \geq 0, x_{2} \geq 0, x_{3} \geq 0$

Multiple Choice

Use the two-stage method to solve.
-Find $x_{1} \geq 0, x_{2} \geq 0, x_{3} \geq 0$ such that
$$\begin{aligned}& x_{1}+2 x_{2}+x_{3} \leq 40 \\& 2 x_{1}+x_{2}+x_{3} \geq 26\end{aligned}$$
And $\mathrm{z}=4 \mathrm{x}_{1}+\mathrm{x}_{2}+2 \mathrm{x}_{3}$ is maximized.

A) $x_{1}=40, x_{2}=0, x_{3}=0, z=160$
B) $x_{2}=20, x_{1}=0, x_{3}=0, z=20$
C) $x_{3}=40, x_{1}=0, x_{2}=0, z=80$
D) $x_{1}=30, x_{3}=15, x_{2}=0, z=135$