The order in which atomic orbitals by electrons are filled is based on the Aufbau principle which states that orbitals are filled in increasing energy level. The answer that applies here is C. The overall energy level of the orbital.
There's no such thing as "an unbalanced force".
When the entire group of forces acting on an object is unbalanced,
meaning that the net force on the object is not zero, then the object
moves with accelerated motion . . . it may speed up, it may slow down,
or its speed may remain constant while its direction changes.
Newton's second law of motion can be formally stated as follows: The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.
The formula for Voltage is V = IR or in words
voltage equals current times the resistance