A Charged Particle Moves with a Constant Speed Through a Region

Multiple Choice

A charged particle moves with a constant speed through a region where a uniform magnetic field is present. If the magnetic field points straight upward, the magnetic force acting on this particle
Will be strongest when the particle moves

A) upward at an angle of $45 ^ { \circ }$ above the horizontal.
B) straight upward.
C) in a plane parallel to Earth's surface.
D) straight downward.