Using the information in the tool box, if the equations are expressed in the form of $F(kx,ky)$, we get only for option D as a function of zero.
Writing the equation of option D as $dy/dx = y^2/(x^2 -xy-y^2)$
i.e;$ F(x,y) = y^2/(x^2 -xy -y^2)$
$F(kx,ky) =k^2x^2/(k^2x^2 - kxky - k^2y^2) = k^0.F(x,y)$
Hence it is a homogenous function with degree zero.