Which of the following three judgments are known to be true: (1) either A is on a business trip, or B is on a business trip, or C is on a business trip; (2) if A is on a business trip, then C is on a business trip; (3) C is unable to leave because of work. This leads to:. ['A travels but B travels.', 'B travels but A travels.', 'A travels and B travels.', 'A does not travel and B does not travel.']