单项选择题A．Her taking improper sleeping medications.B．Her having unusual stress lately.C．Her having a poor digestion.D．Her having insufficient physical activities.

单项选择题A．To find out whether they take music lessons in their spare time.B．To find out whether they can name four different musical instruments.C．To find out whether they enjoy playing musical instruments in school.D．To find out whether they differ in their preference for musical instruments.