What do US Low Altitude Charts portray?

Low Altitude Charts are specifically designed to provide vital information for Instrument Flight Rules (IFR) operations below 18,000 feet mean sea level (MSL). They portray the airway system, which includes the routes aircraft use for navigation, as well as the associated data necessary for planning and conducting flights under IFR conditions.

These charts feature not only the routes but also show navigational aids such as VORs and NDBs that pilots can use for navigation purposes. Additionally, they include important information about airspace classifications, minimum altitudes, and pertinent data relevant to safe and efficient flight operations at lower altitudes.

This focus on IFR operations below 18,000 feet distinguishes Low Altitude Charts from other types of aeronautical charts, which may cover higher altitudes, different types of airspace, or specific navigational features like GPS waypoints. Thus, option B accurately reflects the primary content and purpose of Low Altitude Charts.