单选题

　　[阅读选择]You can't change your energy cycle， but you can learn to make your life fit it better. Habit can help， Dr. Kleitman believes. Maybe you're sleepy in the evening but you must stay up late anyway. Counteract your cycle to some extent by habitually staying up later than you want to. If your energy is low in the morning but you have an important job to do early in the day， rise before your usual hour. This won't change your cycle， but you'll get up steam and work better at your low point.

　　If one wants to work more efficiently at his low point in the morning， he should _______.

　　A.change his energy cycle

　　B.overcome his laziness

　　C.get up earlier than usual

　　D.go to bed earlier