Which term describes sending or receiving data but not at the same time?

Which term describes sending or receiving data but not at the same time?

• A. Full duplex
• B. Simplex
• C. Half duplex
• D. Polling

Answer: (C)

Half-duplex describes a link where data can go in both directions, but not at the same time. Devices take turns transmitting and listening, so one party must finish or wait before the other can speak. This is like a walkie-talkie, where you press to talk and release to listen. In contrast, simplex is one-way only, and full duplex allows simultaneous sending and receiving. Polling is a control method to grant permission to talk, not a description of the duplex mode.

Half-duplex describes a link where data can go in both directions, but not at the same time. Devices take turns transmitting and listening, so one party must finish or wait before the other can speak. This is like a walkie-talkie, where you press to talk and release to listen. In contrast, simplex is one-way only, and full duplex allows simultaneous sending and receiving. Polling is a control method to grant permission to talk, not a description of the duplex mode.