Suppose You're Trying to Make a Final Exam Schedule for Six

Multiple Choice

Suppose you're trying to make a final exam schedule for six classes: anthropology 107 (A) ,
Economics 212 (E) , information systems 194 (I) , statistics 261 (S) , history 201 (H) , and geology 101
(G) . The graph below shows which classes students have in common: these are connected by edges.
Use graph coloring to find the chromatic number.

A) 3
B) 2
C) 4
D) 5