The given expression is

It can be written as
[ we can add or subtract the same thing]
The expression can be factored as difference of two squares
![16x^(4)-64=[4x]^(2)-(8)^(2)=(4x^(2)+8)(4x^(2)-8)](https://img.qammunity.org/2018/formulas/mathematics/high-school/6lrkcpwu8jjr6gewyb6fzwpujn0oa1dqqm.png)
The common factor of the two terms is 16
WE can take 16 as common factor:
=

Options 1 ,3,4 are the equivalent expressions.