Which of the following best defines the term "non-group displacement"? A. A reduction in the size of a group's room block based on previous experience with the group. B. The number of rooms a group occupies that could have been occupied by transient travelers at a higher rate. C. A central reservation system error in which a guest is booked into the wrong hotel. D. A reservation error caused by the hotel's failure to update the central system about its room availability.