【正确答案】
【答案解析】[听力原文] Calendar In the modem calendar, we label all years with B.C. or A.D. / There is no 'zero' year / —in this system, the year when Christ was born is 1 A.D., / and the year preceding it is 1 B.C. / This practice was first suggested in the sixth century A.D., / and was adopted by the pope of that time. / It took quite a while for it to become a worldwide standard, however. / Russia and Turkey, for example, did not convert to the modern calendar and year scheme until the 20th century.