A circuit contains an electrical power supply, a lamp, an ammeter, and a variable resistor. The resistance of the variable resistor is increased. What happens to the ammeter reading, and what happens to the brightness of the lamp?
A) The ammeter reading decreases, and the lamp's brightness increases.
B) The ammeter reading increases, and the lamp's brightness increases.
C) The ammeter reading decreases, and the lamp's brightness decreases.
D) The ammeter reading increases, and the lamp's brightness decreases.