A massless, rigid, insulating rod of length \(R\) is attached at one end to a wall by a hinge so that it is free to swing vertically. The other end of the rod is attached to a sphere of mass \(m\) with charge -\(Q\). If the rod and sphere are released in a horizontal position, which of the following electric fields is required to maintain the horizontal position of the rod?

W) mg/Q, down

X) mg/Q, up

Y) mgQ/R, down

Z) mgR/Q, up
W) mg/Q, DOWN