Correct option is D
Contour Line: A contour line is an imaginary outline of the terrain obtained by joining its points of equal elevation.
Characteristics of Contour: The following point are consider which are as follows:
All points in a contour line have the same elevation;
Flat ground is indicated where the contours are widely separated and steep-slope where they run close together.
A uniform slope is indicated when the contour lines are uniform spaced (i.e. tends to parallel each other).
A plane surface when they are straight parallel and equally spaced.
A series of closed contour lines on the map represent a hill, if the higher values are inside.
