Which statement about smoke detectors is correct?

The choice stating that smoke detectors can sense smoke particles even when they are not visible is correct. Smoke detectors are designed to respond to the presence of particles in the air, which can include smoke from a fire. This means that even when smoke is not dense enough to be easily seen by the naked eye, smoke detectors can still detect it, allowing for an early warning.

This capability is crucial for fire safety, as many types of fires produce smoke before they are visible or produce significant heat. The ability to detect invisible smoke can provide valuable time for occupants to evacuate and for emergency responses to be initiated, potentially preventing injuries and property damage.