What does the term Dolby B or Dolby C printed on tape recorders and other sound systems refer to ?

Both DC and AC power can be used

What does the term Dolby B or Dolby C printed on tape recorders and ot

1.	What does the term Dolby B or Dolby C printed on tape recorders and other sound systems refer to ?
A.	Frequency modulated system
B.	Amplitude modulated system
C.	Nose reduction circuit
D.	Both DC and AC power can be used
Answer» D. Both DC and AC power can be used