Asymbol on a compass or map that is circular with graded points for the direction is commonly known as a
a) grid system
b)scale
c)legend
d)compass rose

Actually, I believe that is a compass rose. I did scale and it was wrong.

A Compass Rose is the one that shows the directions on a Map which involves the Cardinal directions such as north, south, east, and west as well as the Intermediate directions such as northeast, southeast, southwest, and northwest. Sometimes, It is also called as a wind-rose or Rose of the Winds. So we can say that symbol on a compass or map that is circular with graded points for the direction is commonly are known as the compass rose