After Landing on an Unexplored Klingon Planet,Spock Tests for the Direction

Multiple Choice

After landing on an unexplored Klingon planet,Spock tests for the direction of the magnetic field by firing a beam of electrons in various directions and by recording the following observations:
Electrons moving upward feel a magnetic force in the northwest direction.
Electrons moving horizontally toward the north are pushed downward.
Electrons moving horizontally toward the southeast are pushed upward.
Mr.Spock therefore concludes that the magnetic field at this landing site is in which direction?

A) toward the east
B) toward the northeast
C) toward the southwest
D) toward the southeast
E) toward the west