问题详情：
After a couple has had their first child, to their disappointment they become infertile (不生育的)and can not have more children . Many couples have difficulties having children, and sometimes it is impossible for couples to have children because they are infertile. Fortunately, cloning would allow these couples to have children. This is one reason why it is difficult to decide whether cloning is ethical（伦理的) or not. The following are some of the reasons why cloning should be allowed.
As just discussed, cloning can be used to help benefit those who cannot have children through the normal, natural way. It is the desire of most couples to have children and when it is impossible to bear children of their own, some are willing to do anything to have a child. Cloning will allow them to have a child or many children that have the genetic（基因的）pattern of the parents.
Through cloning, research can progress. We can learn enough to produce human organs without having to produce human beings. We may develop technology to allow easier genetic testing and fixing problems such as spinal cord injuries, cancer, and many more.
Cloning organs for organ transplants(移植) is one of the major practical reasons that cloning should be allowed. There is always a high demand for organs. Some argue for the cloning of humans to create extra body parts. Others talk of just wanting to clone an organ to replace a faulty organ.
Rejuvenation (返老还童) is also a key argument for advocates of cloning. Human cloning may one day cure heart attacks. Some scientists believe that by injecting cloned healthy heart cells into damaged heart tissue will lead to healing of the heart.
33. The topic of the text is introduced by________.
A. giving an example B. make comparisons
C. setting down general rules D. presenting research finding34. The third paragraph is written to tell us ________ .
A ing can benefit research B. scientific research is progressing
C. human organ are in great demand D. cloning makes genetic testing easier
35. Which of the following best shows the structure of the test?
【回答】
AAD
知识点：阅读理解
题型：阅读理解
