The statement that minimum altitude requirements vary with terrain is true.

• A. Not specified
• B. True
• C. False
• D. Only in winter

Answer: (B)

Minimum altitude requirements are set to guarantee obstacle clearance and are influenced directly by the terrain along a route. When the terrain rises—mountain peaks, ridges, tall man-made structures—the minimum safe altitude must be higher to keep clearance above those obstacles. In flatter areas, the same safety margins allow lower minimum altitudes. This is why charted minima (like minimum enroute altitudes or other IFR minimums) vary from one area to another: they’re tailored to the highest terrain along the path and the need to maintain safe clearance. The season doesn’t change these requirements; they’re based on terrain and obstacle clearance, not weather or time of year.