An electron (mass=9.1 x 10-31; charge=-1.6 x 10-19C) experiences no deflection if subjected to an electric field of 3.2 x 105 V/m and a magnetic field of 2.0 x 10-3 Wb/m2 . Both the fields are normal to the path of electron and to each other. If the electric field is removed, then the electron will revolve in an orbit of radius:
(A) 45m
(B) 4.5m
(C) 0.45m
(D) 0.045m
