Before takeoff and after landing, the status of the outflow valve should be _____, and the cabin should be _____.

The correct answer indicates that the outflow valve should be open and the cabin should be depressurized before takeoff and after landing. This is essential for maintaining safe cabin pressure levels during these critical phases of flight.

When the outflow valve is open, it allows for the proper venting of air from the cabin to achieve a depressurized state. During takeoff and landing, the cabin is typically at ambient pressure, which helps prepare for a seamless transition in and out of altitude pressures. Maintaining a depressurized cabin is crucial for passenger comfort and safety when the aircraft is on the ground, as it minimizes the risk of rapid pressure changes that could cause discomfort or injury.

The other options suggest situations that are not appropriate for the operational phases mentioned. For instance, having the outflow valve closed would not allow for proper ventilation and could lead to unsafe pressure buildup, while maximum differential pressure is more relevant to cruising conditions, not ground operations. Likewise, maintaining cabin pressure at sea level or specific temperature imbalances during these phases would not align with the normal operational procedures of an aircraft, as they do not accommodate the need for a depressurized state essential for takeoffs and landings.