( 64 )^ - 2/3 × ( 1/4 )^ - 2 is equal to ?

Answer: Option A

$$\begin{array}{rl}& \text{6}{\text{4}}^{-\frac{2}{3}}\times {\left(\frac{1}{4}\right)}^{-2}\\ & ={\left(4^3\right)}^{-\frac{2}{3}}\times {\left(\frac{1}{4}\right)}^{-2}\\ & =4^{-2}\times {\left(\frac{1}{4}\right)}^{-2}\\ & ={\left(\frac{1}{4}\right)}^2\times {\left(\frac{1}{4}\right)}^{-2}\\ & ={\left(\frac{1}{4}\right)}^{2-2}\\ & ={\left(\frac{1}{4}\right)}^0\\ & =1\end{array}$$