Jeffrey is playing a game with the two spinners below in the attachment:

jeffrey will win a prize if the sum of the two spinners is an even number. what are all of the possible outcomes of spinning the two spinners?

a. {3, 6, 9, 12}
b. {1, 2, 3, 4, 6, 8}
c. {3, 4, 5, 6, 7, 8, 9, 10, 11, 12}
d. {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12}