Final answer:
The ending of the crew rest period before landing varies by airline and is governed by specific regulations, so the exact duration (30 mins, 45 mins, 1 hour, or 1.5 hours) should be confirmed with the relevant airline or regulatory body.
Step-by-step explanation:
The question relates to the specific policies or regulations regarding crew rest period for airline staff before landing. The timing of when the crew rest should end before the plane lands is not universally stated here, and it can vary depending on airline carrier and specific regulations. Therefore, without a particular reference to an airline's crew resource management manual or regulatory body guidelines, the answer could be any of the provided options (30 minutes, 45 minutes, 1 hour, or 1.5 hours).
For many airlines, the duration of the crew rest period before they are required to be on duty can differ based on the length of the flight, time zones crossed, and the nature of their work onboard the aircraft. It is important to consult the specific airline's operations manual or the aviation regulator for the correct answer as this could be critical for compliance with safety regulations.