AMC8 1994 Problem 22

The two wheels shown at the right are spun and the two resulting numbers are added. The probability that the sum of the two numbers is even is
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Answer Choices
A. \dfrac{1}{6}
B. \dfrac{1}{4}
C. \dfrac{1}{3}
D. \dfrac{5}{12}
E. \dfrac{4}{9}