A. It is a process of converting data into analog signals optimized for transmission
B. It is a process of converting data into electrical signals optimized for transmission
C. It is a signal
D. None of them

A. Pulse modulation
B. Analog modulation
C. Digital modulation
D. All the above

A. Speech
B. Audio
C. Video
D. All the above

A. Electrical current
B. Electronic sign
C. Electromagnetic
D. None of them

A. Bi cable
B. Coax
C. Electric cable
D. Both b and c

A. Telephone line
B. Optical fiber
C. Coaxial cable
D. All the above

A. Receivers
B. Modems
C. Radio receivers
D. All the above

A. Recording
B. Broadcasting
C. Visual media display
D. All the above

A. 20 to 20000Hz
B. 30 to 3000Hz
C. 20 to 20000Hz
D. 200 to 20000Hz

A. Sound
B. Heat
C. Light
D. All the above