题目

High -speed trains, Zhi Fu Bao, shared bikes and online shopping are considered as the new Four Great Inventions of China by young foreigners, according to a video survey by Beijing Foreign Studies University. In the video ,young people from 20 countries were asked to talk about the great inventions that had influence their lives in China. Here are 4 young people's . opinions.SamI' m from Romania. China is really great country and its high - speed railways are very fast, comfortable and tidy. It takes me only about 6 hours from Beijing to Shanghai by train. It saves a lot of time and it is che已知,则的值为(       ). A.                B.               C.               D.