单选题 Even though trading in ivory has been outlawed by international agreement, some piano makers still use ivory, often obtained illegally, to cover piano keys. Recently, experts have devised a synthetic ivory that, unlike earlier ivory substitutes, has found favor with concert pianists throughout the world. But because piano makers have never been major consumers of ivory, the development of the synthetic ivory will therefore probably do little to help curb the killing of elephants, from whose tusks most natural ivory is obtained.
Which one of the following, if true, most helps to strengthen the argument?

A、 Most people who play the piano but are not concert pianists can nonetheless easily distinguish between the new synthetic ivory and inferior ivory substitutes.
B、 The new synthetic ivory can be manufactured to resemble in color and surface texture any of the various types of natural ivory that have commercial uses.
C、 Other natural products such as bone or tortoise shell have not proven to be acceptable substitutes for natural ivory in piano keys.
D、 The most common use for natural ivory is in ornamental carvings, which are prized not only for the quality of their workmanship but also for the authenticity of their materials.
E、 (E) It costs significantly less to produce the new synthetic ivory than it does to produce any of the ivory substitutes that scientists had developed previously.

【正确答案】 D

【答案解析】[解析] 根据合成象牙对抑制捕杀大象的活动收效甚微可以推出，合成象牙可能在许多方面无法替代自然象牙，(D)给出了这种可能性，因此(D)为正确答案。