Flying over a desert area in an airplane, two scientists looked down with trained eyes at trees and bushes．After an hour’s flight one of the scientists wrote in his book, “Look here for probable mental．” Scientists in another airplane, flying over a mountain region, sent a message to other scientists on the ground, “ Gold possible”．Walking across hilly ground, four scientists reported, “This ground should be searched for metals．” From an airplane over a hilly wasteland a scientist sent back by radio one word, “Uranium”
None of the scientists had X-ray eyes; they had no magic power for looking down below the earth’s surface．They were merely putting to use one of the newest methods of locating minerals in the ground—using trees and plants as sighs that certain minerals may lie beneath the ground on which the trees and plants are growing．
This newest method of searching for minerals is based on the fact that minerals deep in the earth may affect the kind of bushes and trees that grow on the surface．
At Watson Bar Creek, a brook six thousand feet high in the mountains of British 39, however, one tends to believe fully in the reality of the dream world, Columbia, Canada, a mineral search group gathered bags of tree seeds．Boxes were filled with small branches from the trees．Roots were dug and put into boxes．Each bag and box was carefully marked．In a scientific laboratory the parts of the forest trees were burned to ashes and tested．Each small part was examined to learn whether there were minerals in it．
Study of the roots, branches, and seeds showed no silver．But there were small amounts of gold in the roots and a little gold in the branches and seeds．The seeds growing nearest to the tree trunk had more gold than those growing on the ends of the branches．
If the tree had not indicated that there was gold in the ground, the scientists would not have spent money to pay for digging into the ground．They did dig and found more gold below．They dug deeper．They found large quantities of gold．
1．Scientists were flying over a desert or a hilly wasteland or a mountain region in order to search for __________．
A．gold B．silver C．metals D．minerals
2．The study of trees, branches and roots indicates that ________
A．there were larger amounts of gold in the branches than in the seeds
B．there were smaller amounts of gold in the roots than in the branches
C．there were larger amounts of gold in the seeds growing nearest to the tree trunk than seeds growing on the ends of branches
D．there were more gold in the branches than in the roots
3．Which is the best title suggested below?
A．Scientists Searching for Metals with Special Power
B．New Methods of Searching for Minerals
C．Gold Could Be Found by Trees and Plants
D．A New Method of Searching for Minerals –Using Trees and Plants
4．Which of the following is NOT mentioned as part of a tree that can help find minerals?
A．Leaves B．Roots C．Branches D．Seeds
5．The scientists were searching for minerals by using ________．
A．X-ray B．Magic power
C．a special instrument D．trained eyes