下列运算正确的是 $($ 　　 $)$

A．	$\sqrt{72}·\sqrt{\frac{1}{288}}=\sqrt{\frac{72}{288}}=\pm \frac{1}{2}$
B．	${\left(a{b}^2\right)}^3=a{b}^5$
C．	$(x-y+\frac{4\mathit{xy}}{x-y})(x+y+\frac{2\mathit{xy}-2y^2}{y-x})={(x+y)}^2$
D．	$\frac{3c^2}{8\mathit{ab}}÷\frac{-15a^{2}c}{4\mathit{ab}}=-\frac{2c}{5a}$