Examine the scenario.

A stream of negatively-charged particles is moving to the right in a magnetic field. The particles experience a force downward.

Which situation(s) would result in the particle stream experiencing an upward force?

(Select all that apply.) (I think you have to select 2?)

a) using uncharged particles moving to the right

b) using positively-charged particles moving to the left

c) using positively-charged particles moving to the right

d) using negatively-charged particles moving to the left