CEMC Pascal, 2008

Combinatorics Difficulty 3.0 AMC 10/12 Find the answer Canada

Five circles are drawn on a piece of paper and connected as shown. Each circle must be coloured red, blue or green. Two circles connected by a straight line may not be coloured the same. How many different ways are there to colour the circles?

(A) $24$ (B) $60$ (C) $72$ (D) $36$ (E) $48$

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