What actions must be taken if a pilot encounters severe weather unexpectedly?

The correct choice emphasizes the importance of assessing the situation and adjusting the flight path as necessary while maintaining communication with Air Traffic Control (ATC). When a pilot unexpectedly encounters severe weather, the safety of the flight is paramount.

Assessing the situation involves evaluating the current weather conditions to determine the best course of action. This could mean altering altitude, changing the route, or even delaying descent or approach to avoid hazardous weather. Communication with ATC is crucial because they can provide updated information about the weather and offer assistance, such as rerouting and giving traffic advisories, which can aid in avoiding further complications.

The other options do not present a comprehensive approach to mitigating the risks associated with severe weather. Maintaining altitude and notifying passengers might not be sufficient if the weather conditions require immediate action. Attempting to land without proper assessment could lead to dangerous situations, especially if the landing environment is affected by severe weather. Disconnecting the autopilot and returning to the origin may also not be the most strategic response without first evaluating the current situation and available options.