How long does it take before no movement is sensed according to the alarm system?

The correct choice reflects the standard time duration set for the alarm system to recognize the lack of movement and activate an alert. After 30 seconds of no movement being detected, the alarm system triggers, which ensures safety for individuals by raising an alarm or triggering an emergency response.

This timing is critical in emergency situations, such as fires, where a quick response is essential. It allows for a balance between preventing unnecessary alarms from minor movements and ensuring that an alarm is raised in a timely manner if someone becomes incapacitated or unable to respond. The choices of 15 seconds, 1 minute, and 2 minutes do not align with the typical settings implemented for safety and quick response, which is why they are less appropriate in this context.