D
Sciencecan'texplainthepowerofpets,butmanystudieshaveshownthatthecompanyofpetscanhelplowerbloodpressure(血压)andraisechancesofrecoveringfromaheartattack,reducelonelinessandspreadall-roundgoodcheer.Anyownerwilltallyouhowmuchjoyapetbrings.Forsome,ananimalprovidesmorecomfortthanahusband/wife.A2002studybyKarenAllenoftheStateUniversityofNewYorkmeasuredstr ess(紧张)levelsandbloodpressureinpeople-halfofthempetowners–whiletheyperformed5minutesofmentalarithmetic(算术)orheldahandinicewater.Subjectscompletedthetasksalone,withahusband/wife,aclosefriendorwithapet.Peoplewithpetsdiditbest.Thosetestedwiththeiranimalfriendshadsmallerchangeinbloodpressureandreturnedmostquicklytobaselineheartr ates.Withpetsintheroom,peoplealsomadefewermathmistakesthanwhendoinginfrontofothercompanions.Itseemspeoplefeelmorerelaxed(放松)aroundpets,saysAllen,whothinksitmaybebecausepetsdon'tjudge.Astudyreportedlastfallsuggeststhathavingapetd ognotonlyraisesyourspiritsbutmayalsohaveaneffectonyoureatinghabits.ResearchersatNorthwesternMemorialHospitalspentayearstudying36fatpeopleandtheirequallyfatd ogsondiet-and-exerciseprograms;aseparategroupof56peoplewithoutpetswereputonadietprogram.Onaverage,peoplelostaboutI1pounds,or5%oftheirbodyweight.Theirdogsdidevenbetter,losinganaverageof12pounds,morethan15%oftheirbodyweight.Dogownersdidn'tloseanymoreweightthanthosewithoutd ogsbut,sayresearchers,gotmoreexerciseoverall-mostlywiththeirdogs-andfounditworthdoing.
67.Whatd oesthetextmainlydiscuss?
A.Whatpetsbringtotheirowners.
B.Howpetshelppeoplecalmdown.
C.People'sopinionsofkeepingpets.
D.Pet'svalueinmedicalresearch.
正确答案:A


