阅读下列材料，从每题所给的四个选项(A、B、C和D)中，选出最佳选项。
A
Opera at Music Hall：1243 Elm Street. The season runs June through August, with additional performances in March and September. The Opera honors Enjoy the Arts membership discounts. Phone：2412742.http：//www. cityopera. com.
Chamber Orchestra：The Orchestra plays at Memorial Hall at 1406 Elm Street, which offers several concerts from March through June. Call 7231182 for more information. http：//www. chamberorch. com.
Symphony Orchestra：At Music Hall and Riverbend. For ticket sales, call 3813300.Regular season runs September through May at Music Hall and in summer at Riverbend. http：//www. symphony. org/home. asp.
College Conservatory of Music (CCM)：Performances are on the main campus (校园) of the university, usually at Patricia Cobbett Theater. CCM organizes a variety of events, including performances by the wellknown LaSalle Quartet, CCM's Philharmonic Orchestra, and various groups of musicians presenting Baroque through modern music. Students with I. D．cards can attend the events for free. A free schedule of events for each term is available by calling the box office at 5564183.http：//www. ccm. uc. edu/events/calendar.
Riverbend Music Theater：6295 Kellogg Ave. Large outdoor theater with the closest seats under cover (price difference). Big name shows all summer long! Phone：2326220.http：//www. riverbendmusic. com.
21．Which number should you call if you want to see an opera?
A．2412742. B．7231182. C．3813300. D．2326220.
22．When can you go to a concert by Chamber Orchestra?
A．February. B．May. C．August. D．November.
23．Where can students go for free performances with their I. D. cards?
A．Music Hall. B．Memorial Hall.
C．Patricia Cobbett Theater. D．Riverbend Music Theater.
