Do you find getting up in the morning so difficult that it's painful? This might be called laziness, but Dr. Kleitman has a new explanation. He has proved that everyone has a daily energy cycle. During the hours when you labour through your work, you may say that you're "hot". That's true. The time of day when you feel most energetic is when your cycle of body temperature is at its peak. For some people that peak comes during the forenoon. For others it comes in the afternoon or evening. No one has discovered why this is so, but it leads to such familiar monologues  as "Get up , John ! You'll be late for work again !" The possible explanation to the trouble is that John is at his temperature-and-energy peak in the evening. Much family quarrelling ends when husbands and wives realize what these energy cycles mean, and which cycle each member of the family has. You can't change your energy cycle, but you can make your life fit it better. Habit can help. Dr. Kleitman believes. Maybe you're sleepy in the evening but feel 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 . Get off to a slow start which saves your energy. Get up with a yawn and stretch. Sit on the edge of the bed a minute before putting your feet on the floor. Avoid the troublesome search for clean clothes by laying them out the night before. Whenever possible, do routine work in the afternoon and save tasks requiring more energy for your sharper hours . The text is probably taken from a   _  .
news report research paper medical textbook fashion journal
Question: Do you find getting up in the morning so difficult that it's painful? This might be called laziness, but Dr. Kleitman has a new explanation. He has proved that everyone has a daily energy cycle. During the hours when you labour through your work, you may say that you're "hot". That's true. The time of day when you feel most energetic is when your cycle of body temperature is at its peak. For some people that peak comes during the forenoon. For others it comes in the afternoon or evening. No one has discovered why this is so, but it leads to such familiar monologues  as "Get up , John ! You'll be late for work again !" The possible explanation to the trouble is that John is at his temperature-and-energy peak in the evening. Much family quarrelling ends when husbands and wives realize what these energy cycles mean, and which cycle each member of the family has. You can't change your energy cycle, but you can make your life fit it better. Habit can help. Dr. Kleitman believes. Maybe you're sleepy in the evening but feel 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 . Get off to a slow start which saves your energy. Get up with a yawn and stretch. Sit on the edge of the bed a minute before putting your feet on the floor. Avoid the troublesome search for clean clothes by laying them out the night before. Whenever possible, do routine work in the afternoon and save tasks requiring more energy for your sharper hours . The text is probably taken from a   _  .
A. news report
B. research paper
C. medical textbook
D. fashion journal
Answer: