HW Score: 40%, 6 of 15 points Question 4, 7.2.17 O Points: 0 of 1 Write the resulting set using the listing method. {1,2, 7}U{1,6, 7} . . . . . Select the correct choice below and, if necessary, fill in the answer box to complete your choice. O A. {1,2,7}U{1,6,7} = (Use a comma to separate answers as needed.) O B. {1,2,7}U{1,6,7} is the empty set