题目内容：

With rapid advances in medical science, cloning is slowly but surely looking like it could be in our near future. However, is it really an option that should be considered as a way to extend human life?

Reproductive cloning may help human families gain children, but there's also a benefit for the animal world. It brings hope to people eager for children but unable to have their own or adopt. It can also bring about the recreation of species that have long since died, allowing scientists to fully study the species as a living creature instead of simply looking at images or bones.

Many believe that cloning can be used to replace failing organs. This will reduce the waiting list for organ donations and allow more people to be saved. Not only that, but because the organ is, in fact, your own organ, there would be less chance of rejection.

Cloning could prove helpful in genetic research. Using cloning technologies, genetic researchers would have a better understanding of the composition of genes and the effects of genetic constituents (成分) on human characters. There's also the possibility of changing genetic constituents in cloned humans, and cloning could help fight genetic diseases.

While the cloning of body organs can help extend human life, it could also cause a lot of malpractice (玩忽职守). Along with the ability to clone desired characters, there could be the possibility of people deliberately reproducing undesired characters. This could lead to a rise in malpractices within society.

Cloning involves a process of creating identical genes. As such, there would be a lack of diversity in humankind. Scientists believe this lack of diversity will lower the human race's ability to adapt.

Whatever your view on cloning may be, studies show that the clone would in fact not be completely identical to the original just as twins are not completely identical. Though they might look alike, twins have different personalities and enjoy different things. The same could be said of clones. Even if technology were created in which your memories and thoughts could be transmitted (传送) to the clone, your clone would still be a different person.

1.What good might reproductive cloning bring?

A. It may help improve human well-being.

B. It could contribute to the rising birthrate.

C. It could help animals survive deadly diseases.

D. It may enable scientists to better study extinct species.

2.According to the text, cloning can also be used for       .

A. organ transplant

B. solving the aging problem

C. infectious disease treatment

D. constructing a gene database

3.What's one problem cloning may cause?

A. Great diversity.

B. Individual security risk.

C. Increased improper conduct.

D. Serious personality disorder.

4.Why are twins mentioned in the last paragraph?

A. To stress twins' similarities.

B. To show twins are quite common.

C. To carry out deeper research on twins.

D. To better illustrate what a clone will be like.