A solid magenta line bounding an area on a sectional chart typically indicates the boundary of:
Why →
A solid (filled/shaded) magenta line or shaded area on a sectional chart indicates Class E airspace that begins at 700 feet AGL. Surface-based Class E uses a dashed magenta pattern. MOAs use hatched magenta borders with specific labeling.The trap →
Choice A is surface Class E, which is the dashed magenta pattern. The solid/dashed distinction is one of the most-tested chart vocabulary items.SOURCE → FAA Aeronautical Chart User's GuideCHECKED APR 21ACS II.A.K2EASY