根据短文内容，从短文前方框内的选项中选出能填入空白处的最佳选项，并在答题卡上将该项涂黑。如果选项为E，则涂A和B两项。

A.  If the ring is far from the other rings, then we are sure that lots of sunny and rainy weather happened. B. Looking at the tree rings is more important. C. It is also expected that little sunlight or rainfall would limit （限制） the growth of the tree. D.  However, many centuries ago, a lot of people lived there. E.  He decided that the people had to leave because they had cut down all the trees.

 
Do you want to know something about the history of the weather? Don’t look at the sky. Don’t look for old weather report.     Some weather reports go back only century, but some trees can show us an exact record of the weather even further back.
It’s clear that a tree would grow best in a climate with lots of sunlight and rainfall.  
The change from a favorable to an unfavorable climate can be seen by reading the tree rings in a tree trunk (树干). To find out the weather years ago, count the rings of a tree trunk from the outside to the inside.    If the rings are close together, then the climate was bad for the tree.
Studying tree rings is important not only for the history of weather, but also for the history of man. In a place of New Mexico you can find only sand ---no trees and no people.      They left suddenly. Why?
A scientist studied the dead tree rings which had grown there.      . Trees were used for making fires and building houses. So, after the people cut down all the trees, they had to move.