How can smart sensors help save energy?

By automatically switching devices off when not in use

Smart sensors measure conditions such as movement, occupancy, temperature, light level or equipment status. The governing concept is demand-based automation: energy is supplied when a service is needed and reduced when it is not. For example, an occupancy sensor can switch off lights in an empty room, and a control system can place an idle device into a low-power mode. This lowers unnecessary electricity consumption without requiring constant manual checking. Thus, option B is correct. Keeping every device on continuously wastes energy, while polluting water and burning waste are harmful actions unrelated to sensor-based energy management. Sensors save energy through accurate detection and automatic control, not by damaging the environment.

This is a Class 11 Artificial Intelligence question. Chapter: Employability Skills. Topic: Unit 5: Green Skills - IV.