题目内容：
InParagraph 5, what does the research study suggest about divided sleep?
A．Divided sleep is a strange way to sleep. A．Divided sleep is a strange way to sleep.
B．Divided sleep is a natural sleep pattern for human.
B．Divided sleep is a natural sleep pattern for human.
C．Divided sleep occurs when people sleep with artificial lights.
C．Divided sleep occurs when people sleep with artificial lights.
D．Divided sleep means sleeping 11 hours in one period.
D．Divided sleep means sleeping 11 hours in one period.
参考答案：
答案解析：