問(wèn)題補(bǔ)充:?jiǎn)芜x題百米賽跑終點(diǎn)計(jì)時(shí)員必須在看到發(fā)令槍冒白煙時(shí)就開(kāi)始計(jì)時(shí),而不能聽(tīng)到槍聲再開(kāi)始計(jì)時(shí),這是因?yàn)?
A.離起跑線太遠(yuǎn),怕聽(tīng)不清槍聲
B.聽(tīng)槍聲計(jì)時(shí)不準(zhǔn)確,使運(yùn)動(dòng)員成績(jī)偏低
C.看煙計(jì)時(shí)比較方便
D.聽(tīng)槍聲計(jì)時(shí)不準(zhǔn)確,使運(yùn)動(dòng)員成績(jī)偏高
答案:D