Which products result in a difference of squares? check all that apply.

(x – y)(y – x)
(6 – y)(6 – y)
(3 + xz)(–3 + xz)
(y2 – xy)(y2 + xy)
(25x – 7y)(–7y + 25x)
(64y2 + x2)(–x2 + 64y2)

The right answer for the question that is being asked and shown above is that: "(3 + xz)(–3 + xz); (y2 – xy)(y2 + xy); (64y2 + x2)(–x2 + 64y2)." The products that will result to a difference of squares include (3 + xz)(–3 + xz); (y2 – xy)(y2 + xy); (64y2 + x2)(–x2 + 64y2)

The correct answer would be C.