Which altitude provides operational safety concerning obstacle clearance in mountainous areas?

The correct answer pertains to Grid Minimum Off-Route Altitude (MORA), which is designed specifically for ensuring operational safety in mountainous and obstacle-rich environments. MORA provides a defined altitude that accounts for the highest terrain and various obstacles over a specific grid area on aeronautical charts. By adhering to MORA, pilots can maintain a safe vertical distance from potential hazards, thus enhancing safety during navigation, especially in areas where terrain might not be well marked or expected.

In contrast, while the Minimum Safe Altitude and the general idea of being a certain distance above obstacles are important safety considerations, they do not offer the comprehensive protection that Grid MORA provides across potentially variable landscapes. FL200, or Flight Level 200, represents a specific altitude that may not necessarily account for local obstacles, particularly in mountainous terrain. Therefore, relying solely on a specific flight level like FL200 without considering local conditions could pose safety risks.

Thus, the appropriateness of Grid MORA in mountainous areas makes it the optimal choice for obstacle clearance and operational safety.