Which of the following would always increase the flow of current through the lights in the circuit shown above?

a. Decreasing the battery voltage and increasing the resistance of the lights.
b. Increasing the battery voltage and increasing the resistance of the lights.
c. Increasing the battery voltage and decreasing the resistance of the lights.
d. Decreasing the battery voltage and decreasing the resistance of the lights.

c. Increasing the battery voltage and decreasing the resistance of the lights.