根据以下内容，回答211-214题。 SummerTravelSale NorthSunAirlinesisproudtobringyouitsannualSummerTravelSale!Asusual,fightsbe-tweenselectedcitiesintheU.S.andCanadaareonsaleforaslowas$44eachway.Faresthislowcan'tlastlong,sovisitourwebsiteorcallacustomerserviceoperatorandbookyourticketstoday! PricesbelowapplytotravelbeginningMay21st,2006.TravelmustbecompletedbyOctoberlst,2006.TicketsmustbepurchasedbyMay1sttobeeligibleforthesale. SampleOne-waySummerSalesFares MinneapolistoWinnipeg$44 PittsburghtoToronto$64 SacramentotoVictoria$64 OmahatoDenver$94 DetroittoOttawa$94 ClevelandtoToronto$94 TorontotoDallas$94 ColumbustoQuebecCity$104 PhiladelphiatoOttawa$104 SanJosetoSanAntonio$114 WhatistrueaboutNorthSunAirlines?
A.It offers worldwide flights B.It is based in the United States C.It holds a sale every summer D.It sells cheap round-trip tickets正确答案C
