Answer:
Correct Answer is: Contour lines with V-shape
Step-by-step explanation:
Contour lines are Isolines that connect points with the same elevation, these lines depending on their form can determine some landforms or useful data of the terrain by just looking at them. For example, circular or radial contour lines could tell us there is a depression or a peak.
In this case, rivers can also be determined by just looking at the contours, in mountainous regions rivers usually are inside a valley, so if we find V-shaped contour lines going from high elevation to low elevation its probable that there is a river. The V is pointing to the upstream of the river, and the opposite direction is where the river is flowing.