[tex] {x}^{2} - [/tex]which could be the missing term in the expression if a factor of the expression is x-2ya) 2xyb) -2yc) [tex] {4y}^{2} [/tex]d)4y

This is a difference of two squares.
If one factor is
[tex]x+2y[/tex]An the other is
[tex]x-2y[/tex]We have that the expression is:
[tex](x+2y)\cdot(x-2y)=x^2-4y^2[/tex]So the missing term is 4y², option c