Two spherical conductors $A$ and $B$ of radii $1 \mathrm{~mm}$ and $\mathrm{mm}$ are separated by a distance of $5 \mathrm{~cm}$ and are uniformly charged. If the spheres are connected by conducting wire, then in equilibrium condition, the ratio of the magnitude of the electric fields at the surfaces of spheres $A$ and $B$ is
(A) $4: 1$
(B) $1: 2$
(C) $2: 1$
(D) $1: 4$