2^n + 4 - 2 × 2^n2 × 2^ ( n + 3 ) + 2^ - 3 is equal to = ?

Answer: Option D

$$\begin{array}{rl}& \frac{2^{n+4}-2\times 2^n}{2\times 2^{\left(n+3\right)}}+2^{-3}\\ & =\frac{2^{n+4}-2^{n+1}}{2^{\left(n+4\right)}}+\frac{1}{2^3}\\ & =\frac{2^{n+1}\left(2^3-1\right)}{2^{\left(n+4\right)}}+\frac{1}{2^3}\\ & =\frac{2^{n+1}\times 7}{2^{n+1}\times 2^3}+\frac{1}{2^3}\\ & =\left(\frac{7}{8}+\frac{1}{8}\right)\\ & =\frac{8}{8}\\ & =1\end{array}$$