In a topographic map, contour lines that are close together indicates a

This indicates a steep slope or change in elevation

Steep slope

Explanation:

The contour lines are usually defined as the lines of equal height. It represents the vertical height of any place, which is measured in terms of feet or meters. These are used in the topographic map to describe the topography of an area. These lines are always parallel to one another and never intersects with each other.

These contour lines are oriented closely, widely and sometimes they maintain a constant distance of separation.

The close contours represent a steeper slope, whereas wide contours represent a gentle slope.