Of the four (4 types of thematic maps, which one is a map in which ranked classes of some variable are depicted with shaded or colored patterns for predefined zones?

Of the four types of Thematic maps, it is the CHLOROPLETH MAP which is ranked classes of some variable are represented using colored or shaded patterns and placing of symbols for those zones that are predefined. This is to show the average value of a certain property. 

It's probably because some types of violets are blue