B1, B2 and B3 are the three
identical bulbs connected to a battery of steady emf with
key K is closed as shown in the given figure. What will happen
to the brightness of the bulbs B1 and B2 when the key is opened?
ABrightness of the bulb B1 increases and that of B2 decreases.
BBrightness of the bulbs B1 and B2 increases.
CBrightness of the bulbs B1 decreases and that of B2 increases.
DBrightness of the bulbs B1 and B2 decreases.