$\begin{array}{l}{\text{Here, (?)}}^{\text{2}}\times {\text{(12)}}^{\text{2}}÷{\text{(48)}}^{\text{2}}\text{= 81}\\ \\ \text{It can also be written as}\\ \\ {\text{(?)}}^{\text{2}}\times {\left(\frac{12}{48}\right)}^{\text{2}}\text{= 81 }\Rightarrow {\text{(?)}}^{\text{2}}\text{= 81}\times \text{16}\\ \\ \Rightarrow \text{\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}? =}\sqrt{\text{81}\times \text{16}}\Rightarrow =\text{9}\times \text{4 = 36}\end{array}$

Hence, Option E  is correct.