已知全集$U=R,A=\left\{\overline{)x}x\le 0\right\},B\left\{\overline{)x}x\ge 1\right\},$则集合$C_U\left(A\cup B\right)=$（）

A．

$\left\{\overline{)x}x\ge 0\right\}$

B．

$\left\{\overline{)x}x\le 1\right\}$

C．

$\left\{\overline{)x}0\le x\le 1\right\}$

D．

$\left\{\overline{)x}0<x<1\right\}$