Which of the following best describes a PLC’s input module?

A PLC's input module plays a crucial role in its operation by interfacing with the external environment. Specifically, it is responsible for receiving signals from various input devices, such as sensors, switches, and other types of measurement tools. When these input devices generate analog signals—representing physical quantities like temperature, pressure, or flow rate—the input module converts these analog signals into digital signals. This conversion is essential because the PLC operates using digital logic and must receive input in a form it can process.

In this way, the input module enables the PLC to monitor real-world conditions and react accordingly through its programmed logic. This functionality is fundamental to the automation process that PLCs facilitate in various industrial applications. Thus, the characterization of the input module as a component that converts analog signals into digital signals accurately reflects its primary function within the PLC system.