[ 8 - ( 4^9/4 2.2^2 2 2^ - 2 )^^1/2 ] is equal to = ?

Answer: Option D

$$\begin{array}{rl}& \left[8-{\left(\frac{4^{\frac{9}{4}}\sqrt{{2.2}^2}}{2\sqrt{2^{-2}}}\right)}^{{}^{\frac{1}{2}}}\right]\\ & =\left[8-{\left(\frac{2^{2\times \frac{9}{4}}\sqrt{2^{1+2}}}{2\sqrt{\frac{1}{4}}}\right)}^{{}^{\frac{1}{2}}}\right]\\ & =\left[8-{\left(\frac{2^{\frac{9}{2}}{.2}^{\frac{3}{2}}}{2\times \frac{1}{2}}\right)}^{{}^{\frac{1}{2}}}\right]\\ & =\left[8-{\left(2^{\frac{12}{2}}\right)}^{{}^{\frac{1}{2}}}\right]\\ & =\left[8-\left(2^{6\times \frac{1}{2}}\right)\right]\\ & =\left[8-\left(2^3\right)\right]\\ & =\left[8-8\right]\\ & =0\end{array}$$