Part A
Directions: Read the following three texts．Answer the questions on each text by choosing A, B, C or D．Mark your answers on ANSWER SHEET 1.
Meals around the family are less common today than in the past．As a result of small families and working wives, more than half of all Americans eat more than haft their meals away from homes．
The main advantages of this new pattern of American eating are the fast food chains where edible things roll out like car parts on an assembly line．The fast food industry has been growing at a rate of 15 percent a year．Pizza has become a staple(主食), and the hamburger billions sold annually has replaced the hot dog as the American national dish．
In addition to pizza and hamburger, American appetites are regularly whetted by such fast food as fried fish and chicken, French fries, onion tings, soft drinks and shakes．Many of these foods have been attacked by nutritionists and public health physicians because they are high in fat and sugar．But no matter what is said about them by health professionals, the 140 000 fast food companies and shops are likely to continue to prosper and multiply because they are fast, inexpensive, attractive to youngsters and let's be honest millions like the taste of what's dished up．
The main problem with most fast food meals is that they're not nutritionally balanced．Those of pizza, chicken or beef usually contain more than enough protein for a child or for one meal．But for the number of calories they provide—generally more than a third of an 's daily requirements, they tend to oversupply you with fats and salt and to undersupply you with vitamins A and C, several B vitamins and iron．While pizza is one of the better, balanced fast foods, with plenty of protein and less fat than other types of meals, it is especially high in salt content, a negative factor for those who are easy to develop high blood pressure．Fast food meals are also sadly deficient in vegetables(except potatoes) and fruit．Thus a good rule of thumb is to eat salad, vegetables and fruit with your other meals on the days when you eat fast food．
Selecting a nutritious drink at a fast food restaurant is often difficult．Milk and fruit juice( not fruit drink), if on the menu are probably the best choices．
Another pitfall(隐藏的危险) is French fried potatoes．As they come from the ground, potatoes are a nutritional bargain low in fat, high in desirable complex carbohydrates．But when fried in deep fat, potatoes become a high fat, high calorie food．A typical fast food serving of fries contains 200 or more calories, too many of them fat calories.
The author's purpose in writing this article is to ______.