premise: How to read topographic maps<br>Use the thicker contour lines to determine the elevation. Contour lines represent paths or segments of the earth. Topographic maps are covered in contour lines.
hypothesis: Topographic maps only have lines on them.
reason: The text says topographic maps are covered in contour lines, but doesn't say if they only include lines. I'm not sure why the model thought the statement was incorrect, though.