Which two explanations of DTMF dialing are true? (Choose two.)

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Which two explanations of DTMF dialing are true? (Choose two.)

A. DTMF dialing consists of simultaneous voice-band tones generated when a button is pressed on a telephone.
B. The use of DTMF enables support for advanced telephony services.
C. DTMF dialing uses INVITE messages to signal when the first digit is pressed in a new call.
D. DTMF dialing consists of a simultaneous digital-band pulse generated when a button is pressed on a telephone.
E. DMTF dialing is based on rows and columns of Low frequency modulation. There are 4 rows, and 5 columns, with 2 farthest right columns and being used for reserved applications.