152. Mouth cancer is a danger for people who rarely brush their teeth. In order to achieve early detection of mouth cancer in these individuals, a town’s public health officials sent a pamphlet to all town residents,describing how to perform weekly self-examinations of the mouth for lumps. Which of the following, if true, is the best criticism of the pamphlet as a method of achieving the public health officials’ goal? (A) Many dental diseases produce symptoms that cannot be detected in a weekly self-examination. (B) Once mouth cancer has been detected, the effectiveness of treatment can vary from person to person. (C) The pamphlet was sent to all town residents, including those individuals who brush their teeth regularly. (D) Mouth cancer is much more common in adults than in children. (E) People who rarely brush their teeth are unlikely to perform a weekly examination of their mouth. key is E. What's wrong with A? self-examination can not help to detect the symptom, and thus can not achieve the official's goal of early detection of mouth cancer. tks. | 
