What Fundamental Fact Underlies the Operation of Essentially All Electric

What fundamental fact underlies the operation of essentially all electric motors?

A) Opposite electric charges attract and like charges repel.
B) A current-carrying conductor placed perpendicular to a magnetic field will experience a force.
C) Alternating current and direct current are both capable of doing work.
D) Iron is the only element that is magnetic.
E) A magnetic north pole carries a positive electric charge, and a magnetic south pole carries a negative electric charge.