What is the primary purpose of conducting a cabin check every 15 minutes?

Conducting a cabin check every 15 minutes is primarily aimed at ensuring the safety and security of passengers. This regular inspection allows the flight crew to keep an eye on the overall cabin environment, monitor passenger behavior, and identify any potential safety issues that may arise during the flight. By doing so, the crew can address concerns promptly, which is crucial in maintaining a safe environment.

The other options relate to important functions within the cabin but do not encompass the primary reason for the frequency of the checks. Monitoring altitude pressure is typically the responsibility of the flight deck and not something that would be managed during a cabin check. Managing in-flight entertainment systems, while relevant for passenger enjoyment, is not a primary safety concern. Similarly, distributing refreshments is part of cabin service but is secondary to ensuring that all passengers are safe and accounted for. Therefore, the emphasis on safety and security is paramount in justifying the necessity for these frequent cabin checks.