题目内容：
根据以下材料，回答题MyteacherMissBensonwasthekindestcreatureontheearth.IwasgoingtomarryherwhenIgrewup--21shewouldwait.Icouldn'tbeartomissonepreciousmomentofherpresenceby22theclassroom.Ialwaysraisedmyhandswhenshecalledforvolunteerstogather23andbringthemtoher
desk.Thatwasthebestchoreofall.Itmade24gettingnearenoughtoher.Iwouldarrangeandrearrangethepapersuntiltheywereinperfectorder.
Istartedpesteringmymothertoputextrafruit25mylunch.IwasneverbraveenoughtohandittoMissBensondirectly,though.Eachdaythedelicacywasputunobservedonherdesk.
Andthe26wasalwaysthesame.Shewouldcomeinandsitdown."Hownice!"Shewouldpickthefruitup,then27theroom."Whatthoughtfullittlechildbroughtmethis?"Nooneclaimedthe
honor,leastofallme."28itbethatIhaveasecretadmirer?"shewouldask.Iwouldfeeltheredrisinginmyface,andIwouldsighwith29whenMissBensonputthefruitawayandstartedthelesson.
Onemorning,theclasswasexcited.ThenextdaywasMissBenson'sbirthday.Myheartbeatfast--Icouldgivehersomething30.Thatafternoonwasspentcombingforwildflowers.Ifoundseveralkinds.
ThenextmorningIhungbackasotherspresentedtheirgifts.31IwenttothedeskandgavetheflowerstoMissBenson.Shewaspleased,andhelditto32cheekforamoment.
ThenextMonday,MissBensonwasnotinclass.ThenIwas33togototheprincipal'soffice.WhenIarrived,lsawmymother.Onatableweremyflowers.
"Doyouknow34MissBensonistoday?"theprincipalasked."35,sir,"Ianswered.
"MissBenson,"hesaid."isinthehospital,andyousentherthere!"Isat,36,inmychair.
"Doyouknowwhatyougaveher?"hecontinued.I37,"someflowers."
"Theywerepoisonous!"Hewasangry."Howdidyouprotect38whenyoupickedthem?"
"Ididn'tknowtheywerepoisonous."Icried.
Ibeggedmy-mothertotakemetothehospital.MissBensonwasinbedwhenwearrived."Ididn't39tomakeyousick..."Isaid.MissBensonsmiled,"Youwantedtogivemesomethingspecial,didn'tyou?"I
wasfilledwithhappiness.Shewasnotmadatme."AndI'lltellyouasecret,"shecontinued."WhenIammarried,ifIhavea40,Iwouldlikehimtogrowupjustlikeyou."
A．if
B．when
C．since
D．before
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