Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the best answer to each of the questions from 31 to 35.
With a view to shedding new light on the effects of sleeplessness, Randy Gardner, a student in the United States, came up with an experiment for a school science project, in which he stayed awake for over 264 hours. Meanwhile, Dr. William from Stanford University and Gardner's two friends closely observed him.
After 24 hours without sleep, Gardner started having trouble reading and watching television. By the third day, he was all thumbs. By the fourth day, he was hallucinating. Over the next few days, not only did Gardner's speech become so slurred that people could not understand him, but he was also incapable of remembering things. By the eleventh day, Gardner could not pass a counting test, during which he simply stopped counting. He could not remember what he was doing.
When the experiment was over, Gardner slept for 14 hours on end. By the fourth night, he had returned to his normal sleep schedule. Gardner's rapid recovery notwithstanding, scientists believe that going without sleep can be dangerous. They say people should not repeat Gardner's experiment.
Although a person may spend around 25 years sleeping, the purpose of sleep is still shrouded in mystery. The brain was formerly thought to become inactive during sleep, but it turns out to be very in active. Some scientists think that sleep aids the body growth and relieves stress. Whatever the reason, it is vital to get enough sleep.
(Adapted from Select Reading)
Which of the following can be the best title for the passage?