阅读理解。Anewstudyhasfoundnoevidencethatsunscreen,commonlyusedtoreducetheriskofskincancer,actuallyincreasestherisk.ResearchersfromtheUmversityofIowabasedtheirfindingsonarevicwof18earliers

　　阅读理解。 Anewstudyhasfoundnoevidencethatsunscreen,commonlyusedtoreducethe

　　riskofskincancer,actuallyincreasestherisk.

　　ResearchersfromtheUmversityofIowabasedtheirfindingsonarevicwof18earlier

　　studiesthatlookedattheassociationbetweensunscreenuseandmelanoma(黑素瘤).

　　Theysaidthattheyfoundflawsinstudiesthathadreportedassociationsbetweensunscreen

　　useandhigherriskofmelanoma.

　　Mosthealthexpertsbelievethatbyprotectingtheskinfromtheharmfuleffectsof

　　thesun,sunscreenhelpspreventskincancer,whichisincreasinginincidence(发生率)

　　fasterthananyothercancerintheUnitedStates.

　　Butquestionshavebeenraisedaboutsunscreenandwhetheritmayhavetheopposite

　　effect,perhapsbyallowingpeopletoremainexposedtothesunlongerwithoutburning.

　　Theresearcherssaidthatamongtheproblemswithsomeearlierstudiesisthatthey

　　oftenfailedtotakeintoaccountthatthosepeoplemostatriskforskincancer-people

　　withfairskinandfreckles(雀斑),forexample-aremorelikelytousesunscreen.Asa

　　result,itmayappearthatsunscreenusersgetcancermoreoften.

　　Thestudies,whichgenerallyreliedonvolunteerstorecalltheirsunscreenuse,were

　　alsounabletoprovehowwelltheproductshadbeenapplied,Saidthenewstudy.

　　1.Theunderlinedword"flaws"inthe2ndparagraphmostprobablymeans________.A.evidences

　　B.facts

　　C.faults

　　D.failures2.Peoplewithfairskinandfreckles________.A.seldomusesunscreen

　　B.aremoreindangerofskincancer

　　C.canbefreefromtheharmofthesun

　　D.oftenexposethemselvestothesun3.Wecanlearnfromthepassagethat_______.A.sunscreenusersgetskincancermoreoften

　　B.thevolunteershaveprovedtheeffectofsunscreen

　　C.thenewstudywasbasedontheexperiencesofvolunteers

　　D.thenumberofskincancerpatientsisincreasinginAmerica4.Whichoft