3. Which of the following statements is meant by the writer?
A) Ehleringer was successful in his research.
B) Ehleringer failed in his research.
C) Ehleringer can be a successful detective.
D) Ehleringers research proved successful in China.
4. What does the last paragraph tell you?
A) The new technique can tell precisely where a person lives.
B) Water supplied in different regions all come from the same source.
C) Types of water used in different regions provide useful information for the police.
D) Hair samples provide the most important clues to identify crimes.
5. Which of the following is closest in meaning to the title?
A) Human hair may help detectives to solve crimes.
B) Animal hair may help detectives to solve crimes.
C) Detectives watch hairy criminals closely.
D) Most detectives are hair specialists.
答案與題解：
1.B第三段和第六段談到tap water.A、C、D均是文中提到的內容。8是錯誤的，因為文章第六段說，我們飲用的牛奶和軟飲料都含有大量水分，而沒有說tap water是軟飲料。
2.C第四段的問句針對第三段的內容。these watery quirks指的是上段中的unique proportions of the heavier and lighter isotopes of hydrogen and oxygen.所以C是正確答案。
3.A第六段和第七段提供了答案。科學家發現頭發能反映出當地自來水中氫、氧同位素的含量；科學家也已經研究出不同地區水成分是不同的，并且在此基礎上來確定來自不同地區的人的頭發成分。
4.C選項A、B、D與原文均有出入。盡管在一個較大的范圍內，人們使用成分較為相同的水，但是水的成分組成提供的信息可以幫助官方縮小破案線索范圍。
5.A題目的意思是：人的頭發可以幫助偵探破案。