Which sensor type detects environmental changes such as temperature?

The correct answer is a temperature sensor because it is specifically designed to detect and measure changes in temperature within an environment. Temperature sensors can be analog or digital and can operate in various settings, from industrial environments to home automation systems. They work by using different principles, such as resistance changes in materials (thermistors), changes in voltage (thermocouples), or infrared sensing technologies, to provide accurate temperature readings.

In contrast, noise sensors are focused on detecting sound levels; motion sensors detect movement within a particular area; and proximity card readers are designed to identify and authenticate individuals based on their proximity to a reader using RFID technology. Each of these sensors serves distinct functions unrelated to temperature detection, highlighting the unique role of temperature sensors in monitoring environmental changes related to heat.