Answer:
Option (D)
Step-by-step explanation:
Map Key refers to the group of symbols that are used in the maps in order to depict various things like hospitals, roadways, railways, and bridges. These symbols help in understanding where a particular object is located. It makes easier to read a map.
Inside a map key box, the typical information that is provided is the mountains and their highest peaks that are generally shown by some symbols such as triangles. This signifies the highest elevation in any particular area.
Thus, the correct answer is option (D).