two objects are electrically, charged. The net charge on one object is doubled, therefore the electric force
a quadruples
b reverses
c doubles
d divides
c doubles
When the net charge on one object is doubled, the electric force between the two objects will double as well. This is because the electric force is directly proportional to the product of the charges and inversely proportional to the square of the distance between the charges. If one of the charges is doubled, the force will also double.