If\[{{\left[ \frac{{{\mathbf{2}}^{{{\mathbf{n}}^{\mathbf{3}}}\mathbf{-3}{{\mathbf{n}}^{\mathbf{2}}}}}}{\mathbf{2}}\mathbf{.}{{\mathbf{2}}^{\mathbf{3n}}} \right]}^{\mathbf{1/3}}}\mathbf{+}{{\left[ \mathbf{4}\mathbf{.}{{\mathbf{2}}^{{{\mathbf{n}}^{\mathbf{2}}}\mathbf{+2n}}} \right]}^{\mathbf{1/2}}}\mathbf{=640}\], then find the value of n.

• A.  6                                                        
• B.  7
• C.  8        
• D.  10
• E.  None of these