[求助]再请教几道阅读词汇题

hendragom

谢谢。

33. The word "agents" in line 5 is closest in
meaning to  
A). dangers  
B). examples  
C). areas  
D). causes  

48. The phrase “pry off" in line 21 is closest in meaning to  
A). swallow B). remove  C). squeeze  D). locate  

49. The word "littered" in line 22 is closest in meaning to  
A). covered  B). displayed C). fertilized  D). planted  

40. The word "standard" in line 12 is closest in
meaning to
(A) practical (B) customary (C) possible (D) unusual

44.  According to the passage, Grenoble, France, is the place where  
(A)  instruments were developed for measuring certain chemical elements  
(B)  scientists first recorded atmospheric levels of carbon dioxide  
(C)  scientists studied the contents of an ice core from Antarctica  
(D) the relationship between carbon dioxide and temperature was discovered
原文是：Instruments were used to measure the ratio of certain isotopes in the frozen water to get an idea of the prevailing atmospheric temperature at the time when that particular bit of water became locked in te glacier.