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【单选题】

CThe best title for the passage may be ().

A.China--the Native Place of Pandas Forever
B.China’s Efforts to Clone Pandas
C.China’s First Cloned Panda
D.Exploring the Possibility to Clone Pandas

A.
C
B.
With only about 1,000 pandas left in the world, China is desperately trying to clone the animal and save the enered species. That’s a move similar to what a Texas A&M University researcher has been undertaking for the past five years in a project called "Noah’s Ark".
C.
Dr. Duane Kraemer, a professor in Texas A & M’s College of Veterinary Medicine and a pioneer in embryo(胚胎) transfer work and related procedures, says he salutes the Chinese effort and" I wish them all the best success possible. It’s a worthwhile project, certainly not an easy one, and it’s very much like what we’re attempting here at Texas A&M--to save animals from extinction. "
D.
Noah’s Ark is aimed at collecting eggs, embryos, semen(精子) and DNA of enered animals and storing them in liquid nitrogen. If certain species should become extinct, Kraemer says there would be enough of the basic building blocks to reintroduce the species in the future.
E.
It is estimated that as many as 2,000 species of mammals, birds and reptiles will become extinct over the next 100 years. The panda, native only to China, is in er of becoming extinct in the next 25 years.
F.
This week, Chinese scientists said they grew an embryo by introducing cells from a dead female panda into the egg cells of a Japanese white rabbit. They are now trying to implant the embryo into a host animal.
G.
The entire procedure could take from three to five years to complete.
H.
"The nuclear transfer of one species to another is not easy, and the lack of available panda eggs could be a major problem," Kraemer believes. "They will probably have to do several hundred transfers to result in one pregnancy. It take s a long time and it’s difficult, but this could be groundbreaking science if it works. They are certainly not putting any live pandas at risk, so it is worth the effort , "adds Kraemer, who is one of the leaders of the Missyplicity Project at Texas A&M, the first ever attempt at cloning a dog.
I.
"They are trying to do something that’s never been done, and this is very similar to our work in Noah’s Ark. We’re both trying to save animals that face extinction. I certainly applaud their effort and there’s a lot we can learn from what they are attempting to do. It’s a research that is very much needed. \
J.
 
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A.
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A.
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B.
Private Sub Command1_Click()
C.
PI=1
D.
Sign=1
E.
n=20000
F.
For k=3 To n
G.
sign=-sign
H.
PI=PI+sign/k
I.
Next k
J.
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End sub
K.
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A.
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