题目内容：
根据以下材料，回答题Peopleoftensay,"Childrencan'tdomathproblem,it'sbecauseparentscan'tdotheirchildren'shomework."Here'sanexampletoshowwhatImean.
Theotherdaymydaughterbroughthomehermathhomework."Ihavetosubtract(减)
from202,"shesaid.
"It'squiteeasy,"Isaid."Youputthe202overthe179."
"Butweneeda10here.Whereisthe107"
"Idon'tknowwherethe10is.Let'sjustsubtract179from202.Ninefromtwoisthree.Youcarryoneandaddittoseven.Eightfromzeroistwo.Theansweris23."
"Wecan'tdoitthatway.Wehavetousethe10."
"Well,I'mgoingtocallyourteachertoseehowshesubtracts179from202."
Overthetelephone,IsaidthatIwashavingabitoftroublewiththehomeworkshehadgiventomydaughter.Theteachersaid,"Intheright-handcolumn(栏)wehaveunitsofone.Thetwointhatcolumncountsfortwoones.Thezerointhecentercountsforzerotens.Thetwointheleft-handcol-umncountsforhundreds.Areyouclear?"ButIdidn'tthinkIwasclear.
Ihungupandfoundmywaytothemedicinebox.Myheadwasnowhurting.Istartedputtingpillsofmedicineintomymouth."Howmanydidyoutake?"Mywifeasked."ItookoneandthenI
tookanother...Iknowoneandonewastwo,butdon'taskmewhatitisnow."
A．Thedaughterwanted__________theotherday.
B．togiveherfatheralesson
C．toshowhowdifficultmathwas
D．herfathertophoneherteacherD.herfathertohelpherwithherhomework
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