21.City people prefer bottled water

• A、

  in tiny amounts

  
  

• B、

  towards tap water

  
  

• C、

  does harm to the environment

  
  

• D、

  brings more health benefits

  
  

• E、

  with the problem of drought

  
  

• F、

  despite the safety of tap water

  
  

14.The author believes that her vegan diet is____________

• A、

  healthy

  
  

• B、

  cheap

  
  

• C、

  sugar-free

  
  

• D、

  low-salt

  
  

A.The bands contained a name and address.

B.Birds use the earth's magneticfield to navigate too.

C.A map and a compass are often helpful for long trips.

D.They fly thousands of miles from one home to another.

E.They learn the route that the older geese have traveled before. 

F.They have answered many questions about how birds navigate.