Which of the following describes a function of a thermocouple?

A thermocouple primarily functions by converting temperature differences into a corresponding voltage. This principle is based on the Seebeck effect, which occurs when two dissimilar metals are joined at two different junctions. When there is a temperature difference between these junctions, a voltage is generated that is proportional to the temperature difference. This feature makes thermocouples particularly useful for measuring temperatures in various applications, including refrigeration systems.

In contrast, measuring the resistance of materials, regulating electrical flow in circuits, or filtering electrical signals are functions associated with other types of sensors or devices. For instance, resistance measurements are typically performed by ohmmeters or other types of temperature sensors, while circuit regulation and signal filtering would involve components like resistors, capacitors, or transistors, none of which describe the primary purpose of a thermocouple.