题目选项分析

Veterinarians generally derive some of their income from selling several manufacturers' lines of pet-care products. Knowing that pet owners rarely throw away mail from their pet's veterinarian unread, one manufacturer of pet-care products offered free promotional materials on its products to veterinarians for mailing to their clients. Very few veterinarians accepted the offer, however, even though the manufacturer`s products are of high quality.

Which of the following, if true, most helps to explain the veterinarian`s reaction to the manufacturer`s promotional scheme?

【选项】Many pet owners have begun demanding quality in products they buy for their pets that is as high as that in products they buy for themselves.