4. Which of these are vestigial structures? A. The wings of a butterfly
B. The hip bones found in some species of snake
C. The thick fur and layer of fat of some mammals in cold climates
D. The sharp spines of a cactus

where's the diagram?

in cartography, a contour line (often just called a "contour") joins points of equal elevation (height) above a given level, such as mean sea level. a contour map is a map illustrated with contour lines, for example a topographic map, which thus shows valleys and hills, and the steepness or gentleness of slopes.

explanation:

b.false that your answer