Choose A, B, C, or D to indicate the sentence that is closest in meaning to each of the following questions: Passengers are not permitted to use their mobile phones during the flight. 

• A. 
  Passengers needn’t use their mobile phones during the flight.
• B. 
  Passengers mustn’t use their mobile phones during the flight.
• C. 
  Passengers shouldn’t use their mobile phones during the flight.
• D. 
  Passengers wouldn’t use their mobile phones during the flight.