题目内容：
Questionsarebasedonthefollowingpassage
CanyouimaginehowyouwouldfeelifyoufelldangerouslyillandcouldnotreachorCalladoctor?Millionsofpeople(I)theworldareinthisunfortunate(2),livingindistantplaces(3)therearenorailways,noproperroadsandnotelephones.Thousandsof(4)arelosteveryyear(5)couldhavebeensavedifmedicalattention(6)intime.
(7)todayhelpcouldbebroughtquicklyandeasily(8)manyofthesepeople(9)fulladvantagewastaken(I0)theaeroplane.(11)countryhasprovedthis(12)thanAustralia.TheAustralians(13)greateruseoftheaeroplanethanany(14)peopleintheworld.Innoothercountry(15)thetotalnumberofmilesflownbythe(16)personsohigh.Infact,ithasbeen(17)thatAustraliansjumpintoplane(18)peopleinothercountriesjumpintotrainsandbuses.Itisnotsurprising,(19),thatAustraliashouldhavebeenthefirstcountry(20)aFlyingDoctorService.
第（1）题选 A．on
B．through
C．allover
D．within
参考答案：
答案解析：