Directions: There are 4 passages in this part. Each of the passage is followed by 5 questions or unfinished statements. For each of them there are 4 choices marked A, B, C and D. Choose the best one and mark your answer on the ANSWER SHEET with a single line through the center.If one wants to work more efficiently at his low point in the morning, he should ______. A．go to bed earlierB．overcome his lazinessC．change his energy cycleD．get up earlier than usual