In any function where microphone, amplifier and speakers are used ofte – McqOptions

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1.	In any function where microphone, amplifier and speakers are used often one would hear a humming sound, which increases in volume gradually. This is due to:
A.	Positive feedback between microphone and speaker
B.	Negative feedback between microphone and speaker
C.	Inadequate frequency response of amplifier
D.	Noise pickup (50 Hz) from power supply
Answer» B. Negative feedback between microphone and speaker

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