阅读理解 There is a growing concern throughout the world that the use of stem-cell research, the process whereby certain cells are extracted from fetuses for future cloning purposes, may lead to a moral dilemma on the nature of cloning technology.
Indeed, certain professionals in the field of cloning will likely face a difficult moral choice in the near future. Embryonic cells are currently extracted from aborted fetuses and then used to generate organs that replace missing or diseased ones in humans. The potential for such swapping of injured or missing limbs is enormous. Amputated arms and diseased livers could be replaced by newly cloned ones by adapting such embryonic cells. However, certain anti-abortion groups have already decried the use of aborted fetuses and pledged to boycott any more such research.
In the United States, President Bush recently signed an executive order banning the use of any Federal money for the purpose of human cloning. However, many political observers note that private research into human cloning continues unabatedly and that, even if the United States supported and managed to enforce an outright ban in both the public and private sectors, competition from other countries would put pressure on US firms to develop their own cloning technology.
A new option has recently been developed to weaken opposition to cloning efforts. New research has uncovered the use of similar stem-cells in fat tissue. The use of such tissue is not as politically volatile since it avoids the issue of abortion. Moreover, proponents of such cloning technology often cite the enormous benefits to medical science that reproductive cloning could reap. Cloning technology could finally cure certain diseases and ailments that are currently untreatable.
However, the prospect of playing god with human genetics has made many weary of pursuing human or partial human cloning. As the successful cloning of Dolly the sheep proved, human cloning may only be a few decades away. For many, the ethical and legal consequences of responding to new technologies that advance the field of cloning have been difficult. Can governments, citizens and private groups come to a consensus on the use and limitations of cloning? Or will we end up with a new generation of monsters, spawned from our desire for eternal life?

单选题 16.In paragraph 3, some political observers note that Bush's executive order may be ineffective because______.

单选题 17.The first two sentences in the second paragraph tell us that the author is______.

【正确答案】 C

【答案解析】属态度推断题。第二段第一、二句指出：事实上，一些专门从事克隆工作的人士可能不久就会面临一个道德上的困难选择。现在是从夭折的胎儿体内取出未发育成熟的细胞用来生成器官，以替换人体缺损的或患病的器官。显然，第二句是对第一句的解释说明。由此可判断，作者对克隆技术的态度只是不偏不倚地提供信息(即选项C正确)；不是支持(选项A)，也没有因为宗教因素而被激怒(选项B)，更不是悲观态度(选项D)。

单选题 18.Certain groups oppose stem-cell research because______.

【正确答案】 D

【答案解析】属事实细节题。相关信息在第二段最后一句(一些反堕胎组织谴责使用夭折的胎儿，并发誓要阻止进一步的有关研究)；此外，这一点也可从第一段的内容得到验证(全世界现在越来越关注干细胞研究，即从胎儿中抽取细胞进行克隆的过程，由此引出一个关于克隆技术的性质的道德难题)。由此可知，选项D正确。其他选项在文章中都没有涉及。

单选题 19.The text is mainly about______.

【正确答案】 C

【答案解析】属主旨思想题。文章第一段指出现状：克隆技术的性质引发道德难题。第二段阐述具体事实以及反对方的意见；第三段介绍政府的干预；第四段给出了支持克隆技术一方的观点，即给人类带来的好处；最后一段提出克隆技术可能带来的后果。由此可知，选项C正确。选项D、B、A分别在第三、四段及最后一段中提到，概括不够全面。

单选题 20.The author refers to a potential new generation of monsters to______.

【正确答案】 A

【答案解析】属概念推断题。题目中的关键词new generation of monsters出现在文章最后一句：难道我们因为想获得永生而最终不惜催生出新一代的怪物来吗?从本句所在的上下文来看，它是对本段第三句的举例说明：推进克隆技术的每一步所产生的道德和法律后果都是很严重的。由此可知，选项A正确(指克隆人存在的潜在危险)。其他选项都推理有误。