At a given instant in time, an electron and a proton are moving directly toward each other at the same speed in a uniform magnetic field that is oriented 90° from the velocities of the particles. They experience magnetic forces which are:
A. equal in magnitude but perpendicular to each other.
C. equal in magnitude but opposite in direction.
D. in opposite directions and differing in magnitude by a factor of 1840.
E. in the same direction and differing in magnitude by a factor of 1840.