已知集合 $A=\left\{x\left|x^2-x-2>0\right.\right\}$ ，则 ${\complement }_{R}A=$ (　　)

A．	$\left\{x\left|-1<x<2\right.\right\}$	B．	$\left\{x\left|-1\le x\le 2\right.\right\}$
C．	$\left\{x\overline{)x}<-1\right\}\cup \left\{x\overline{)x}>2\right\}$	D．	$\left\{x\overline{)x}\le -1\right\}\cup \left\{x\overline{)x}\ge 2\right\}$