题目内容：
What is the perfect condition forsleep?
A．A quiet room with flashing lights. A．A quiet room with flashing lights.
B．bright room with white curtains.
B．bright room with white curtains.
C．A cool room with comfortable pillows.
C．A cool room with comfortable pillows.
D．A dark room with electronic devices.
D．A dark room with electronic devices.
参考答案：
答案解析：