Statement 1: If three identical bulbs are connected in series as shown in figure, then on closing the switche bulb C is short circuited and hence illumination of bulbs A and B decreases.
Statement 2: Voltage on A and ,B decreases.
When switch S is closed, bulb C is short circuited, so voltage V distributes only in two parts i.e., voltage on Bulb A and B increases as compared previously. Hence, illumination of bulb A and B increases.