What is the range, in hertz, of the normal human hearing?
A. 10 Hz to 10 kHz
B. 20 Hz to 20 kHz
C. 2000Hz
D. 40 Hz to 40 kHz
A. 10 Hz to 10 kHz
B. 20 Hz to 20 kHz
C. 2000Hz
D. 40 Hz to 40 kHz