Test: Exam 1 Question 3 of 8 Let U = {16, 17, 18, 19, 20, 21, 22) and A = (16, 17, 19, 20). Find A' . Select the correct choice below and, if necessary, fill in the answer box to complete your answer. O A. A' = (Use a comma to separate answers as needed.) O B. A' is the empty set. app.honorlock.com