Imagine you are sitting in a chamber with your back to one wall. An electron beam, moving horizontally from back wall towards the from wall, is deflected by a strong magnetic field to your right side. What is the direction of the magnetic field?
A. Vertically upwards
B. vertically downwards
C. horizontal perpendicular to the direction of motion of the elctron beam
D. horizontal and parallel to the direction of motion of the electron beam
