A、Clothing. B、Electrical appliances. C、Travel agencies. D、Photographic equipment. B

W: Mr. Smith, is the number of complaints increasing or decreasing?
M: There was a slight decrease last year. The highest number of complaints was two years ago when we received 7,300.
W: Does the reduction mean that the quality of goods and services is improving?
M: I don’t think so. It’s probably due to the poor economic situation. Most people are simply buying less.
W: Is there any change in the nature of the complaints?
M: Not really. People are still complaining about the same things.
W: What do they complain about most often?
M: Electrical appliances. Last year, we received 1,809 complaints about them—25% of all complaints. Then there are complaints about travel agencies, photographic and sound equipment, and clothing—in that order.
W: What sort of complaints do you get about travel agencies?
M: Oh, they include anything from air tickets to accommodation.
W: Are most of the complaints justified?
M: About 90% of the complaints about travel agencies are justified. In other areas, investigation of about 50% of the complaints reveals some kind of business malpractice, but overall about 30% of the complaints are due to misunderstandings on the part of the consumer: the rest are too vague to be worth following up.
W: How long does it take you to complete an investigation of a complaint?
M: About 2 to 3 weeks for a proper investigation. We really need more staff.
W: Thank you, Mr. Smith.
M: My pleasure.
27. Which of the following is the closest to the record number of consumer complaints?
28. Which has the most complaints of all?
29. In general, what’s the proportion of complaints that cannot be investigated?
30. How long do most complaints take to investigate?