The symmetric difference of sets A = {1, 2, 3, 4, 5, 6, 7, 8} and B = {1, 3, 5, 6, 7, 8, 9} is

• A. {1, 3, 5, 6, 7, 8}
• B. {2, 4, 9}
• C. {2, 4}
• D. {1, 2, 3, 4, 5, 6, 7, 8, 9}