PASCAL 2014 Problem 22

A rectangular flag is divided into four triangles, labelled Left, Right, Top, and Bottom, as shown. Each triangle is to be colored one of red, white, blue, green, and purple so that no two triangles that share an edge are the same color. How many different flags can be made?

Image

Answer Choices
A. 180
B. 200
C. 220
D. 240
E. 260