题目内容：
Questionsarebasedonthefollowingpassage:
Afterabusydayofworkandplay,thebodyneedstorest.Sleepisnecessaryforgoodhealth.
Duringthistime,thebodyrecoversfromtheactivitiesofthepreviousday.Therestthatyougetwhilesleepingenablesyourbodytoprepareitselfforthenextday.
Therearefourlevelsofsleep,eachbeingalittledeeperthantheonebefore.Asyousleep,yourmusclesrelaxlittlebylittle.Yourheartbeatsmoreslowly,andyourbrainslowsdown.Afteryoureachthefourthlevel,yourbodyshiftsbackandforthfromonelevelofsleeptotheother.
Althoughyourmindslowsdown,fromtimetotimeyouwilldream.Scientistswhostudysleepstatethatwhendreamingoccurs,youreyeballsbegintomovemorequickly(althoughyoureyelidsareclosed).ThisstageofsleepiscalledREM,whichstandsforrapideyemovement.
Ifyouhavetroublefallingasleep,somepeoplerecommendbreathingveryslowlyandverydeeply.Otherpeoplebelievethatdrinkingwarmmilkwillhelpmakeyoudrowsy.Thereisalsoanoldsuggestionthatcountingsheepwillputyoutosleep.
Agoodtitleforthispassageis（ ）. A．Sleep
B．GoodHealth
C．Dreams
D．WorkandRest
参考答案：
答案解析：