Question: Broad Top is a plateau located in south-central Pennsylvania bounded to the east by what long, steep, narrow mountain ridge in the Ridge-and-Valley (or Allegheny Mountains) physiographic province of the Appalachian Mountains?
Sentence (from "North Fork Mountain"): North Fork Mountain is a quartzite-capped mountain ridge in the Ridge and Valley physiographic province of the Allegheny Mountains (or "High Alleghenies" or "Potomac Highlands") of eastern West Virginia, USA.
Relevant evidence: No