Scientists have created a tomato that can grow on salty water. The plant is the first crop of its kind ever produced in the worl

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问题     Scientists have created a tomato that can grow on salty water. The plant is the first crop of its kind ever produced in the world.
    Its significance can not be overestimated (高估). The new technology can help mankind solve the problem of feeding its ever-expanding population. It is estimated that by 2025 the world population will amount to more than 9 billion, an increase of 3 billion over 2000. Each day 240,000 more people are born, ready to be fed like the rest of us. Unfortunately, not all the land on Earth can be used to grow crops for humans. About 24.7 million acres of the problem is irrigation (灌溉). When farmers water their crops, salts in the water also enter the soil. Over time, salts such as sodium (钠) and calcium (钙) build up to such a point that they severely harm the growth of crops. Salts destroy most plants’ ability to draw up water through their roots.
    But, the new variety of tomato produced by American and Canadian scientists can store salts in its leaves so that the fruit doesn’t taste salty. Researchers hope this technology will enable areas of poor-quality land to become productive (多产的). And they can feed some of the world’s growing population.
The world "significance" (Para. 2) means ______.

选项 A、importance
B、quality
C、price
D、quantity

答案A

解析 推断题。短文第二段第一句是第二段的主旨句,也就是论点。下面的内容都是解释说明并论证第一句的。第二段整段都是在讲这项新技术的重要性。所以可以推断significance的意思应该是选项A。
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