与 $(\sqrt{2},-\sqrt{3})$ 垂直的单位向量是 $(\quad)$
A. $\pm\left(\frac{\sqrt{3}}{5}, \frac{\sqrt{2}}{5}\right)$
B. $\pm\left(\frac{\sqrt{2}}{5}, \frac{\sqrt{3}}{5}\right)$
C. $\pm\left(\frac{\sqrt{10}}{5}, \frac{\sqrt{15}}{5}\right)$
D. $\pm\left(\frac{\sqrt{15}}{5}, \frac{\sqrt{10}}{5}\right)$