题目内容：
阅读下列短文,回答题目.In period of the summer hofidays there will be a revised schedule(修改过的时刻表)of setvices for the students.Changes for dining-room and library service hours and for bus schedules willbe posed on the wall outside the dining-hall.Weekly film，and concert schedules，which are beingarranged(安排)，will be posted each Wednesday outside the student club.
During the summer holidays，buses going to the town centre will leave the main hall everyhour on the half hour during the day.The dining-room will serve three meals a day from 7:00 a.m.to 7:00 p.m.during the week and two meals from noon to 7:00 p.m.on weekends.The librarywill continue its usual hours during the week，but:has shorter hours on Saturdays and Sundays.Theweekend hours are from noon to 5:00 p.m.
All students who want to use the library lending services must have a new summer card.Thisannouncement will also appear in the next week’s student newspaper.
The:main purpose of this text is to__________. A．tell students of important schedule changes
B．tell students of new bus and library services
C．show the excellent services。for students
D．ask students to renew their library cards
参考答案：
答案解析：