Multiplexing involves sharing a medium by combining multiple signals in which domains?

• A. Time Division Multiplexing
• B. Frequency Division Multiplexing
• C. Code Division Multiplexing
• D. All of the above

Answer: (D)

Multiplexing lets several signals share the same medium by separating them in different dimensions. In time-domain multiplexing, signals take turns and use distinct time slots, so only one signal is on the line at a time. In frequency-domain multiplexing, each signal occupies a separate frequency band within the same channel, allowing all to be transmitted simultaneously without interference. In code-domain multiplexing, signals are spread with unique codes, letting many transmissions share the same frequency band and be separated at the receiver by the code. Since each domain—time, frequency, and code—provides a valid way to multiplex, all of the above are correct.