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  3. It takes a long time to grow a tree. How long? Well, pine trees are the quickest growing trees, but still, they take twenty year

It takes a long time to grow a tree. How long? Well, pine trees are the quickest growing trees, but still, they take twenty year

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问题     It takes a long time to grow a tree. How long? Well, pine trees are the quickest growing trees, but still, they take twenty years to reach a size suitable for cutting and harvesting. An oak takes about sixty years to grow to a good size. A redwood may take hundreds of years.
    Lumber companies, which make their money on trees, depend on those that grow quickly. There- fore, they are always looking for methods to make trees grow faster. So far, the secret to fast growing trees seems to lie in "super-seeds." These are seeds that are gathered from the quickest growing trees in a forest.  One company searched 100,000 acres of trees and selected the seeds from just fifteen trees. These two ounces of seed were enough to plant several hundred new trees.  Eventually, when these trees have grown, seeds will again be taken only from the fastest growing trees of crop. This process of artificial selection will yield, in the future, a super-tree that will grow in half the time it takes normal trees to develop.
    Unfortunately, it takes a long time for a plan like this to reach its goal. The Weyerhauser Lumber Corporation, which started its first collection of seed in 1958, is just now beginning to harvest the super-seeds of the first generation of the faster growing trees.
Super-trees ______.
选项 A、will be a great benefit to lumber companies
B、make extra-good lumber for buildings
C、will probably be weak because of their fast growth
D、may be defenseless to many insects and diseases
答案A
解析 第一段提到木材公司是靠树木赚钱的。第二段提到某个木材公司实施着超级种子的计划。第三段提到某个木材公司已经获得了这个计划的第一代树木。由此可见，树木的快速成材肯定对木材公司有利。选项A是正确的。
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