单选题
"I've never met a human worth cloning." says cloning expert Mark Westhsin from his lab at Texas A&M University." It's a stupid endeavor." That's an interesting choice of adjective, coming from a man who has spent millions of dollars trying to clone a 13-year-old dog named Missy. So far, he and his team have not succeeded, though they have cloned two cows and expect to clone a cat soon. They just might succeed in cloning Missy this spring—or perhaps not for another 5 years. It seems the reproductive system of man's best friend is one of the mysteries of modem science.
Westhusin's experience with cloning animals leaves him upset by all this talk of human cloning. In three years of work on the Missy project, using hundreds upon hundreds of dog's eggs, the A&M team has produced only a dozen or so embryos carrying Missy's DNA. None have survived the transfer to a surrogate mother. The wastage of eggs and the many spontaneously aborted fetuses may be acceptable when you're dealing with cats or bulls, he argues, but not the humans. "Cloning is incredibly inefficient, and also dangerous," he says.
Even so, dog cloning is a commercial opportunity, with a nice research payoff. Ever since Dolly the sheep was cloned in 1997, Westhusin's phone has been ringing with people calling in hopes of duplicating their cats and dogs, cattle and horses. "A lot of people want to clone pets, especially if the price is right," says Westhusin. Cost is no obstacle for Missy's mysterious billionaire owner; he's put up $3.7 million so far to fund A & M's research.
Contrary to some media reports, Missy is not dead. The owner wants a twin to carry on Missy's fine qualities after she does die. The prototype is, by all accounts, athletic, good-natured and supersmart. Missy's master does not expect an exact copy of her. He knows her clone may not have her temperament. In a statement of purpose, Missy's owner and the A&M team say they are "both looking forward to studying the ways that her clones differ from Missy."
Besides cloning a great dog, the project may contribute insight into the old question of nature vs. nurture. It could also lead to the cloning of special rescue dogs and many endangered animals.
However, Westhusin is cautious about his work. He knows that even if he gets a dog pregnant, the offspring, should they survive, will face the problems shown at birth by other cloned animals: abnormalities like immature lungs and heart and weight problems. "Why would you ever want to clone humans, "Westhusin asks," when we're hot even close to getting it worked out in animals yet?/

单选题 By "stupid endeavor" (Line 2, Para. 1), Westhusin means to say that______.
A. animal cloning is not worth the effort at all
B. animal cloning is absolutely impractical
C. human cloning should be done selectively
D. human cloning is a foolish undertaking

单选题 What does the first paragraph tell us about Westhusin's dog cloning project?
A. Its success is already in sight. B. Its outcome remains uncertain.
C. It is doomed to utter failure. D. It is progressing smoothly.

单选题 By cloning Missy, Mark Westhusin hopes to______.
A. study the possibility of cloning humans
B. search for ways to modify its temperament
C. examine the reproductive system of the dog species
D. find out the differences between Missy and its clones

单选题 We learn from the passage that animal clones are likely to have______.
A. a bad temper B. immune deficiency
C. defective organs D. an abnormal shape

单选题 It can be seen that present cloning techniques______.
A. still have a long way to go before reaching maturity
B. have been widely used in saving endangered species
C. provide insight into the question of nature vs. nurture
D. have proved quite adequate for the cloning of humans