16: In recent years, networks of fiber-optic cable have been replacing electrical wire for transmitting telecommunications signals. Signals running through fiber-optic cables deteriorate, and so the signals must be run through a piece of equipment called a regenerator before being transmitted father. Light-Line is the leading manufacturer of signal regenerators. Therefore, Light-line is one of the companies that will most benefit if new long-distance fiber-optic telecommunications networks are constructed.

Which of the following, if true, casts the most doubt on the prediction about light-ling’s prospects?

A: Telecommunications signals sent along electrical wires can travel much farther than signals transmitted through fiber-optic before needing to be regenerated.

B: Expanding its production of regenerators will require Light-line to spend proportionately more on labor and materials.

C: The volume of signals that a fiber-optic cable can carry is several thousand times greater than the volume that can be carried by an electrical wire of similar size.

D: There are technologies that enable telecommunications signals to be transmitted without either wire or fiber-optic cable.

E: Several manufacturers are developing regenerator technologies that will allow signals to be transmitted many times farther than at present before requiring regeneration.

这道题我选了E，但看到不少选B的答案，不知道哪个对请大家发表一下看法

个人认为：题出得不好！明显属于ETS黔驴技穷，开始装神弄鬼。

试着理解：B和E都提出疑问，但哪一个疑问更多呢？E看起来更厉害，但several manufacturers 也许也包括Light-line。这样它也会受益。。。

支持E.

其实，本题的B、D、E初看起来，似乎都有doubt on the prediction 的作用。

但是，仔细分析，结合Therefore, Light-line is one of the companies that will most benefit if new long-distance fiber-optic telecommunications networks are constructed. 应该E最好。

B: 即使仅从利润角度考虑， spend proportionately more on labor and materials仍然可能增加更多的纯利润，比如规模经济等等带来的（当然，其实没必要这样分析的）。

D.如果没有前面的许多论述和结论中的条件（如：networks of fiber-optic cable have been replacing electrical wire for transmitting telecommunications signals. 和 if new long-distance fiber-optic telecommunications networks are constructed.），则D应该能起到很好的削弱结论的作用。

我认为选D,新的技术发展了，都不需要文中所提的技术了，当然企业不能因此盈利了.

我选B项！

我当初是看了一眼E中的Several manufacturers 就把他排了！嗬嗬！因为我已经觉得B对了，这样的排除不免草率！

回过来想想，其实还是这个问题啊！说若干个生产者正在发展新的regenerator technologies ，我觉得这several 不能就此排除LL，说不定LL也正研究呢！这是很有可能的，因为E旨在讲述其他，而未涉及LL！从本质上来讲，他是个无关项！

至于D项，文中很明白的说networks of fiber-optic cable have been replacing electrical wire for transmitting telecommunications signals. D的推理是对文中事实的讨论，是经典的无关选项！

B我也觉得不是很好！但它是的的确确的削弱了LL赚钱的可能！

最后我还想重申一下我对E的看法，主要是我觉得他并没有和LL建立起有效的关系！在对一种商业策略削弱的时候，用到competitor是很常见的，也是很正确的。但是此题中Several manufacturers并没有和LL构成明确的竞争关系，一切的关系都是大家猜得！所以我觉得E不对！

应该是E吧！B是不对的，LL公司本来就是做regeneration的，增加成本是为了获得更多的利润，难道LL没有利润会去增加投入吗？不可能的！D是无关选项，因为题中指出了In recent years, networks of fiber-optic cable have been replacing electrical wire for transmitting telecommunications signals.即使有了新技术，也不是现在马上就用的，目前都用fiber中的tele技术。所以只有E是对的，因为现在tele技术中的signals不需要regeneration了，那么否定了结论！！

说得好。 投入大不能否认利润可以更高。 否则，现在的500强企业不可能追加投资成为现在的样子了，说不定还是作坊呢。呵呵呵 e我也看了很长时间，因为用的是进行时态，正在发展，最大的问题是将来能发展出来吗 谁知道呢。说不定这技术还太不成熟，三年五年都没结果。

但是e也算最好的了 讨that continued production of the drug must inevitably lead to the ibora’s extinction中，continued production是前提，问题是：如果持续生产，将导致灭绝。weaken的方向应该是：即使持续生产，也不会导致灭绝。必须承认出题者的前提。E项反对的是前提，所以不对。that continued production of the drug must inevitably lead to the ibora’s extinction中，continued production是前提，问题是：如果持续生产，将导致灭绝。weaken的方向应该是：即使持续生产，也不会导致灭绝。必须承认出题者的前提。E项反对的是前提，所以不对。