题目内容：
根据以下材料，回答题 StepBackinTime
Doyouknowthatwelivealotlongernowthanthepeoplewhowerebornbeforeus?Onehundredyearsagotheaveragewomanlivedtobe45．Butnow,shecanliveuntilatleast80.
Oneofthemainreasonsforpeoplelivinglongeristhatweknowhowtolookafterourselvesbetter．Weknowwhichfoodsaregoodforus．andwhatwehavetoeattomakesureourbodiesgetallthehealthythingstheyneed．Weknowwhywesometimesgetillandwhattodotogetbetteragain.
Andweknowhowimportantitistodolotsofexercisetokeepourheartsbeatinghealthily.
Butinorderthatwedon'tslipbackintobadhabits,let'shavealookatwhatlifewaslike100yearsago.
Familieshadbetween15and20children,althoughmanybabiesdidn'tlivelong．Childrensufferedfromlotsofdiseases,especiallyrickets(佝偻病)andscurvy(坏血病),whicharebothcausedbybaddiets．Thisisbecausemanyfamilieswereverypoorandnotabletofeedtheirchildrenwell.
ReallypoorfamilieswholivedincrowdedcitieslikeLondonandManchesteroftensleptstandingup,bendingoverapieceofstring,becausetherewasnoroomforthemtoliedown.
Peopledidn'thavefridgesuntilthe1920s．Theykeptfreshfoodcoldbystoringitonwindowsills(窗台板),blocksofice,orevenburyingitinthegarden.
Somechildrenhadtostartworkattheageofsevenoreighttoearnmoneyfortheirparents．Ifyoulived100yearsago,youmightwellbesellingmatchsticks(火柴杆)(ajobdonebymanychildren)orworkingwithyourdadbynow.
Onaveragewomenlivedlongerthanmen100yearsago. A．Right
B．Wrong
C．Notmentioned
参考答案：
答案解析：