题目

Students in America have to get required credits (学分) in order to graduate. The average workload at my school, Hotchkiss, is five courses. But at a school full of overachievers (成绩超过预料的学生), it’s very common to see people taking six or more classes.    I am currently taking six and half classes, including Advanced Placement (AP) Physics, Senior English, AP art, piano (with music history and theory), chorus, US history and AP economics. AP is the more advanced level of courses. It's usually equivalent to first year college courses.    By taking the AP exams in May 某化学兴趣小组为验证Ag、Fe、Cu三种金属的活动性顺序，设计了如下图所示的实验操作。其中可以达到实验目的的组合是（      ）     A．①②或②③或②④⑤                 B．②④或①③或②④⑤          C．①③或②③或①④⑤                D．①②或②③或③④⑤