初中英语完形填空题（2010年黑龙江省大庆市中考英语试题的一道题）Mostpeopleliketotravelonlandbecauseit'salwayssafe.16therearestillsomepeoplewhowanttotravelindangerousplaces.OneoftheseplacesistheAr

　　初中英语完形填空题（2010年黑龙江省大庆市中考英语试题的一道题）

　　Mostpeopleliketotravelonlandbecauseit'salwayssafe.16therearestillsomepeoplewhowanttotravelindangerousplaces.OneoftheseplacesistheArcticOcean(北冰洋).

　　Mendonot17theArctic：Oceanveryoften.Itis18clanger.Itisdarkandcoldthereinwinter...Theiceisdangerous,19.Especiallyinsummertheicebreaksandmoves20.

　　InFebruary,JohnWilliamstartedtocrosstheArcticOcean.Hewentwiththreemenandseveraldogs.Thedogspulledthesledge(雪橇)overtheice,andonthesledgetherewasfoodandsome21thingsforthem.Theytraveledslowly22months.

　　Inthesummertheicebroke,sothey23stopandwaitforthecolddaystocome.Thenwhentheicewashard,theystartedthejourneyagain.Theystayedonabigpieceofice.Theicemovedinwindandtookthemtothe24.Duringtheirjourney,a25droppedsomefoodforthem.OnApril6,theyreachedtheNorthPole(北极）.Thentheytraveledtothesouth.TheycamebackandreachedthelandonMay29.

　　25.A.shipB.planeC.trainD.sledge

　　我想问25为什么选B不选D?从哪句话看出来要选B?