The correct answer is C: Electric force.
Electric force is a force interacting between static electrically charged particles and it is defined by Coulomb's law: F=k*q1*q2/r²
F is the force
k is Coulomb's constant
q1 and q2 are two charged particles
r is the distance between q1 and q2
F can be negative if the force between the charges is attractive (the charges have opposite signs) or F can be positive if the force between charges is repulsive (the same signed charges).