单选题 9.Platinum is a relatively rare metal vital to a wide variety of industries. Xagor Corporation, a major producer of platinum, has its production plant in a country that will soon begin imposing an export tax on platinum sold and shipped to customers abroad. As a consequence, the price of platinum on the world market is bound to rise.
Which of the following, if true, tends to confirm the conclusion above?

A、 An inexpensive substitute for platinum has been developed and will be available to industry for the first time this month.
B、 The largest of the industries that depend on platinum reported a drop in sales last month.
C、 The producers of platinum in other countries taken together cannot supply enough platinum to meet worldwide demand.
D、 Xagor produced more platinum last month than in any previous month.
E、 New deposits of platinum have been found in the country in which Xagor has its production plant.

【正确答案】 C

【答案解析】Argument Evaluation
Situation Xagor Corporation produces platinum, a rare metal vital to many industries. Xagor's plant is in a country that will soon impose an export tax on platinum. The world market price of platinum is predicted to rise.
Reasoning Which of the pieces of information given, if true, would most tend to confirm the prediction given? The conclusion of the argument is a causal prediction: the world market price of platinum will increase because of the export tax on platinum. The argument tells us that a wide range of industries need platinum, so the introduction of taxes on exported platinum would likely make that platinum more expensive for the importing industries. This, in turn, would likely raise the world market price of platinum. But what if those industries could get all their platinum from countries that did not tax platinum exports? Then the world market price might not rise if exports from those countries could adequately fulfill market demand.
A This information tends to undermine the reasoning and does not confirm the conclusion. If a less expensive platinum-substitute were to be developed, the world market price of platinum would tend to decline.
B This information somewhat weakens support for the conclusion. It suggests that overall demand for platinum might decline, at least temporarily, which would tend to lower the world market price of platinum.
C Correct. This information strengthens the support for the conclusion. It indicates that some platinum subject to the export tax will almost certainly be exported and will cost importers more than before. This would tend to cause the world market price of platinum to rise, especially since platinum producers in other countries could remain competitive and still raise their prices.
D This information could indicate a possible upswing in platinum production, which could increase the total world supply of platinum. If the supply increased relative to world demand, the world market price of platinum could decrease, not increase as the argument's conclusion predicts.
E This information suggests a possible increase in the world market supply of platinum, which would tend to reduce the world market price, provided world demand for platinum did not also increase at least proportionately.
The correct answer is C.