问题详情：
PALO AITO, California—“Switching off the television may help prevent children from getting fatter—even if they do not change their diet or increase the amount they exercise,” US researchers said last week.
A study of 192 third and fourth grades, generally aged eight and nine, found that children who cut the number of hours spent watching television gained nearly two pounds(0.91 kg) less over a one-year period than those who did not change their television diet.
“The findings are important because they show that weight loss can only be the result of a reduction in television viewing and not any other activity,” said Thomas Robinson, a pediatrician(儿科专家) at Stanford University.
“American children spend an average of more than four hours per day watching television and videos or playing games, and rates of childhood being very fat have doubled over the past 20 years,” Robinson said.
In the study, presented this week to the Pediatric Academic Societies’ annual meeting in San Francisco, the researchers persuaded about 100 of the students to reduce their television viewing by one-quarter to one-third.
Children watching fewer hours of television showed a significantly smaller increase in waist size and had less body fat than other students who continue their normal television viewing, even though neither group ate a special diet nor took part in any extra exercise.
“One explanation for the weight loss could be the children unstuck to the television may simply have been moving around and burning off calories,” Robinson said.
“Another reason might be due to eating fewer meals in front of the television. Some studies have suggested that eating in front of the TV encourages people to eat more,” Robinson added.
51. The purpose of the first two paragraphs is ______.
A. to report the time children spend watching TV
B. to show that more TV time leads to getting fatter
C. to tell us the best way to reduce weight
D. to introduce the background of the research
52. According to the passage, the time American children usually spend on watching TV ____.
A. is more than four hours a day B. is less than four hours a day
C. doubled in the last twenty years D. is more than on any other activities
53. The time the 100 children spend on TV every day is about _______ in the study.
A. a quarter of an hour B. four hours C. three hours D. one hour
54. Which of the following statements is TRUE according to the passage ?
A. Weight increase owes to the result of a reduction in TV viewing.
B. The percentage of children getting fatter has doubled in the last 20 years.
C. Children usually eat less while watching TV.
D. Children usually eat nothing while watching TV.
55. The main idea of the passage would be ______.
A. less TV time helps reduce children’s weight
B. fewer meals is a must in reducing children’s weight
C. the less you eat, the thinner you will be
D. more exercise is of great benefit to reduce weight
【回答】
DACBA
知识点：新闻报道类阅读
题型：阅读理解
