(单选题)

What can we learn from the passage? ( )

A.Teens will not get off their electronic devices until bedtime.

B.There are more teens who have sleep problems than parents.

C.More than half the teens hide their nighttime electronic use.

D.The teens' body clocks work against the early school start time.

参考答案：D

参考解析：

A项根据electronic devices定位第三段，because their teens won't get off their electronic devices但没有说直到睡觉前都不会离开他们的电子设备，排除A。文中并没有比较青少年和父母的睡眠问题，排除B。C项文中并没有提到超过一半的青少年隐瞒他们夜间使用电子设备的行为，排除C。D项定位第四段they are naturally inclined to go to bed later and sleep later in the morning. But an early school start time doesn't allow it.他们自然倾向于晚睡，早上晚睡，但是提前上学是不允许的，D项正确。故本题正确答案选D。

知识点：推断题英语阅读理解通用英语