53. (    )

38. We can know from the information given in the passage that the moon must be about (   ) away from us. 

• A、one million km
  
  

• B、350,000 km
  
  

• C、300,000 km
  
  

• D、400,000 km
  
  

43. The passage is mainly about (   ). 

• A、a group of cold-water-swimming lovers
  
  

• B、the Polar Bears' life in New York
  
  

• C、doctors' ideas about cold-water swimming
  
  

• D、the requirements of the Polar Bear Club