Answer:
A. Some customers presented tickets purchased on a previous day when there wasn't a ticket taker at the theater entrance.
Step-by-step explanation:
The control of selling fresh prenumbered tickets from the last number sold on the previous day is a control that detects tickets sold the previous day.
If tickets were sold on the previous day, they can be reused today. So having a unique number on them is an ideal way to monitor the range of tickets issued today.
Only those within the range will be allowed to enter the theatre.