One reason why we know that magnetic fields are not the same as electric fields is because the force exerted on a charge +q
选项：

A:is in opposite directions in electric and magnetic fields.
B:is in the same direction in electric and magnetic fields.
C:is parallel to a magnetic field and perpendicular to an electric field.
D:is parallel to an electric field and perpendicular to a magnetic field.
E:is zero in both if the charge is not moving.