A solid magenta line bounding an area on a sectional chart typically indicates the boundary of:
AClass E airspace beginning at the surface
BClass E airspace beginning at 700 feet AGL✓ Correct answer
CA Military Operations Area
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 →Class E beginning at the surface is the dashed magenta pattern. The solid/dashed distinction is one of the most-tested chart vocabulary items.
Field note →Remember: dashed = surface (stricter, authorization required). Solid/shaded = 700 AGL (relaxed). This pattern holds across multiple airspace types.