The ancient Nubians inhabited an area in which typhus occurs, yet surprisingly few of their skeletons show the usual evidence of this disease. The skeletons do show deposits of tetracycline, an antibiotic produced by a bacterium common in Nubian soil. This bacterium can flourish on the dried grain used for making two staples of the Nubian diet, beer and bread. Thus, tetracycline in their food probably explains the low incidence of typhus among ancient Nubians.
Which of the following is an assumption on which the argument relies?
A. Infectious diseases other than typhus to which the ancient Nubians were exposed are unaffected by tetracycline.
B. ！Tetracycline is not rendered ineffective as an antibiotic by exposure to the processes involved in making bread and beer.
C. Typhus cannot be transmitted by ingesting bread or beer contaminated with the infectious agents of this disease.
D. Bread and beer were the only items in the diet of the ancient Nubians which could have contained tetracycline.
E. Typhus is generally fatal.
答案选B
40.
A manufacturer of workstations for computer-aided design seeks to increase sales to its most important corporate customers. Its strategy is to publish very low list prices for workstations in order to generate interest among the buyers for those corporations.
Which of the following, if characteristic of the marketplace, would tend to cause the manufacturer’s strategy to fail?
A. The proposed list prices would seem low to a typical buyer for the manufacturer’s most important corporate customers.
B. The capabilities of workstations suitable for given jobs are not significantly different among various manufacturers.
C. The manufacturer’s most important corporate customers employ as buyers persons who are very knowledgeable about prices for workstations for customer-aided design.
D. Customers differ significantly in the percentage of resources they can devote to computer workstations.
E. Buyers for corporations that purchase workstations for computer-aided design receive bonuses for negotiating large discounts from the list price.
