33. Fast-food restaurants make up 45 percent of all restaurants in Canatria. Customers at these restaurants tend to be young; in fact, studies have shown that the older people get, the less likely they are to eat in fast-food restaurants. Since the average age of the Canatrian population is gradually rising and will continue to do so, the number of fast-food restaurants is likely to decrease.
Which of the following, if true, most seriously weakens the argument?

A、 Fast-food restaurants in Canatria are getting bigger, so each one can serve more customers.
B、 Some older people eat at fast-food restaurants more frequently than the average young person.
C、 Many people who rarely eat in fast-food restaurants nevertheless eat regularly in restaurants.
D、 The overall population of Canatria is growing steadily.
E、 As the population of Canatria gets older, more people are eating at home.

【正确答案】 D

【答案解析】 Argument Evaluation
Situation In Canatria, the older people get, the less likely they are to eat in fast-food restaurants. The average
age of Canatrians is increasing.
Reasoning What evidence would most weaken the support provided by the cited facts for the prediction that the
number of fast-food restaurants in Canatria is likely to decrease? The argument implicitly reasons that
since studies have shown that Canatrians tend to eat in fast-food restaurants less as they get older,
and since Canatrians are getting older on average, the proportion of Canatrians eating in fast-food
restaurants will decline. The argument assumes that this means the overall number of fast-food
restaurant customers will decline and that demand will decrease enough to reduce the number of
fast-food restaurants that can sustain profitability. Consequently, fewer new fast-food restaurants
will open or more old ones will close, or both. Thus, the number of fast-food restaurants in
Canatria will fall. Any evidence casting doubt on any inference in this chain of implicit reasoning
will weaken the argument.
A This strengthens the argument by providing additional evidence that the total number of fast-food restaurants will decrease. If the average number of customers per fast-food restaurant is increasing, then fewer fast-food restaurants will be needed to serve the same—or a lesser—number of customers.
B Even if a few individuals do not follow the general trends described, those trends could still reduce the overall demand for and number of fast-food restaurants.
C The argument is only about fast-food restaurants, not restaurants of other types.
D Correct. This suggests that even if the proportion of Canatrians eating at fast-food restaurants declines, the total number doing so may not decline. Thus, the total demand for and profitability of fast-food restaurants may not decline either, so the total number of fast-food restaurants in Canatria may not decrease.
E If anything, this strengthens the argument by pointing out an additional trend likely to reduce the demand for, and thus the number of, fast-food restaurants in Canatria.
The correct answer is D.