The general value of $\mathrm{x}^{2}+\mathrm{y}^{2}+\mathrm{z}^{2}$ where $\mathrm{x}, \mathrm{y}, \mathrm{z}$ represent a non-zero solution of $\mathrm{x}+2 \mathrm{y}-3 \mathrm{z}=0,2 \mathrm{x}-3 \mathrm{y}+\mathrm{z}=0,3 \mathrm{x}-\mathrm{y}$
$-2 \mathrm{z}=0$ is (where $\lambda$ is an arbitrary constant)
(a) 3
(b) $3 \lambda$
(c) $9 \lambda^{2}$
(d) $3 \lambda^{2}$