The general solution of the differential equation $(1+y)dx-2xdy =0$ is :

$x=C(1+y)^2 $, where C is constant of integration $x^2=C(1+y^2) $, where C is constant of integration $x^2-y^2=C$, where C is constant of integration $y=C+x^2y$, where C is constant of integration

$x=C(1+y)^2 $, where C is constant of integration