Critics of cloning often repeat the question related to the controversial(有争议的) science “Just because we can, does it mean we should?” The closer we come to being able to clone a human, the hotter the debate over it grows. For all the good things cloning may achieve, opponents say that it will do just as much harm. Another question is how to governing cloning process.
There is federal official law banning cloning in the United States, but several states have passed their own laws to ban the practice. The US Food and Drugs Administration(FDA), has also said that anyone in the United States attempting human cloning must first get its permission. In Japan, human cloning is a crime that is punished by up to 10 years in prison.
While laws are to ban cloning at this time, some scientists believe that the technology is not ready to be tested on humans. Ian Wilmut, one of the co-creators of Dolly, has even said that human cloning projects would be an irresponsible crime. Cloning technology is still in its early stages, and nearly 98% percent of cloning efforts end in failure. The embryos are either not suitable for implanting into the uterus(子宫) or they die shortly after birth.
The clones that do survive end up suffering from deadly or problematic genetic abnormalities(畸形). Some clones have been born with faulty heart, lung problems and blood vessel problems. One of the most famous cases was a cloned sheep that was born with but malformed arteries(畸形动脉) leading to the lungs.
Opponents of cloning will point out that we can enthanize(安乐死) these faulty clones of other animals, but they ask what if a human clone is born with these same problems. Advocates of cloning respond that it is now easier to pick out faulty embryos even before they are implanted into the mother. The debate over human cloning is just beginning, but as science advances, it could be the biggest moral dilemma of the 21st century.
68. Which word in the text is the opposite of the underlined word “opponents”?
A. critics B. advocates C. scientists D. co-creators
69. The writer writes this passage mainly to ________________.
A. support passing laws to ban human cloning
B. list problems with human cloning
C. introduce critics’ ideas about human cloning
D. state the debate over human cloning
70. Which of the following will Ian Wilmut probably NOT agree with?
A. Cloning technology is in its early stages.
B. Human cloning should be made illegal.
C. Very few cloning efforts are successful.
D. Cloning technology is ready to be tested on humans