一、语法选择（共15小题；每小题1分，满分15分）
阅读下面短文，按照句子结构的语法性和上下文连贯的要求，从1~15各题所给的A、B、C和D项中选出最佳选项，并在答题卡上将该项涂黑。
Trees are important. They can provide animals ___1___ homes. Lots of products, like paper and pencils, are made ___2___ trees. However, they can give ___3___ these only if they are alive. They must be taken good care of to keep ___4___.
Therefore, people spend much time and money ___5___ trees. It is found that the tree would grow best in a climate with ___6___ sunlight and rainfall, and little sunlight or rainfall would ___7___ the growth of a tree. The change from a favorable to an unfavorable climate ___8___ be decided by reading the pattern of rings in a tree trunk. You should count the rings of a tree trunk ___9___ the outside to the inside. If ___10___ tenth ring is far from the other rings, then it is certain that there is lots of sunlight and rainfall. If the rings are ___11___ to each other, then the climate is bad. Study like this is not only for the history of weather, ___12___ for the history of human beings. You can find only sand now in one place of New Mexico. However, there were ___13___ people who used to live there. They ___14___ suddenly. Why? A group of scientists studied patterns of dead tree rings which once grew there, and they found that people went away because they had destroyed all the trees ___15___ and build houses.
1. A. to B. with C. in D. of
2. A. in B. from C. of D. with
3. A. our B. ours C. we D. us
4. A. healthily B. unhealthy C. healthy D. health
5. A. study B. to study C. on studying D. studying
6. A. many B. few C. a few D. plenty of
7. A. to stop B. stopped C. stopping D. stop
