According to the passage, which of the followingis true about the Space Lab experiment conducted in 1983?答案解析-雷哥GRE

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An experiment conducted aboard Space Lab in 1983 was the first attempt to grow protein crystals in the low-gravity environment of space. That experiment is still cited as evi- dence that growing crystals in microgravity can increase crystal size: the authors reported that they grew lysozyme protein crystals 1,000 times larger than crystals grown in the same device on Earth. Unfortunately, the authors did not point out that their crystals were no larger than the average crystal grown using other, more standard tech- niques in an Earth laboratory.

No research has yet produced results that could justify the enormous costs of producing crystals on a large scale in space. To get an unbiased view of the usefulness of micro- gravity crystal growth, crystals grown in space must be compared with the best crystals that have been grown with standard techniques on Earth. Given the great expense of conducting such experiments with proper controls, and the limited promise of experiments performed thus far, it is questionable whether further experiments in this area should even be conducted.

According to the passage, which of the followingis true about the Space Lab experiment conducted in 1983?

It was the first experiment to take place in themicrogravity environment of space. It was the first experiment in which researchersin space were able to grow lysozyme proteincrystals greater in size than those grown onEarth Its results have been superseded by subsequentresearch in the field of microgravity proteincrystal growth. Its results are still considered by some to beevidence for the advantages of microgravityprotein crystal growth. Its results are considered by many to be invalidbecause nonstandard techniques were employed.

正确答案： D 耗时：