Answer: B)buzzer.
Step-by-step explanation: In case of battery, the chemical energy gets converted into electrical energy.
In case of buzzer, the electrical energy gets converted into sound energy as the buzzer is supplied with electricity to produce an alarming sound.
Motor is a device that converts the electrical energy into mechanical energy .
While in case of switch, its just use to complete or break a circuit so as to put on/off any device.