Answer:
(–7x + 4)(–7x – 4) Sign changes in the middle of both parenthesis , so this will result in difference of squares
Step-by-step explanation:
The formula for difference of squares

(–7x + 4)(–7x + 4) both parenthesis having same terms so this will not result in difference of squares
(–7x + 4)(4 – 7x) both parenthesis having same terms so this will not result in difference of squares
(–7x + 4)(–7x – 4) Sign changes in the middle of both parenthesis , so this will result in difference of squares
(–7x + 4)(7x – 4) sign changes for both terms in both parenthesis so this will not result in difference of squares