B.阅读短文，根据短文内容，从所给的六个选项中选出可以填入空白处的最佳选项，使短文意思完整、连贯。（有两项为多余选项）

  Passage4

  Freedom of riding bicycles

  There isn't any other type of transportation that is as common as bicycles.In China,they have a very long history.But now ,not only in China,bikes are becoming popular in many European countries.__38__

  Bicycles are popular for many reasons.The most important one is prodably its great use in protecting the environment.

  __39__In some European countries,bike-griendly facilities(设施)have helped clear busy roads.As a traditional “cycling capital”,Copenhagen's roads keep bicycles and cars separated（分开）as much as possible.On these routes(路线),there are pre-green lights for cyclists.These kinds of bicycle traffic lights turn green a few seconds before car traffic lights do.It gives the cyclists time to avoid traffic while crossing.

  Cycling also gives people a feeling of freedom.__40__In cities like Amsterdam and Hague ,up to 70 percent journeys are made by bike.To make biking easier,many European cities like Paris and Berlin allow cyclists to bring their bicycles onto subway trains.

  __41__ There are some safety rules you need to follow.Stop at all stop signs and obey red lights just as cars do .Wearing a helmet(头盔)can protect your head if you fall down .If you are cycling with friends,ride in a line.Don't face each other while riding side by side.

  A.However,cycling is not always easy.

  B.They're especially popular among students.

  C.Some young people se e cycling as a fashion.

  D.Cycling is also a great  way to reduce heavy traffic.

  E.That's why many young people choose it as a way to get around the city.

  F.According to the BBC,more bicycles were sold than cars in Europe last year