Which of the following components is required to send faxes via POTS?

A NIC (Network Interface Card) is used for network communication (LAN or internet), not for direct communication over traditional analog telephone lines.

A power supply is necessary to power any computer system, but it is not the specific component responsible for the function of sending faxes via POTS.

A modem (modulator-demodulator) is essential for sending faxes via POTS because it converts the digital data from a computer or fax machine into analog audio signals. These analog signals can then be transmitted over traditional phone lines, and the modem also converts incoming analog signals back to digital data for reception.

A wireless adapter is used for wireless network communication (e.g., Wi-Fi), which is entirely unrelated to sending faxes over a POTS line.