A telephone signal band-limited to 4 kHz is to be transmitted by PCM. If the signal to quantization noise is to be at least 40 dB, the number of levels into which the signal is to be encoded will be

A telephone signal band-limited to 4 kHz is to be transmitted by PCM.

1.	A telephone signal band-limited to 4 kHz is to be transmitted by PCM. If the signal to quantization noise is to be at least 40 dB, the number of levels into which the signal is to be encoded will be
A.	32
B.	64
C.	81
D.	128
Answer» E.