卷烟配方中要求全部使用（）的烟叶。
A.自然醇化或人工发酵
B.新烟或陈烟
C.新烟
D.原烟
参考答案：A
The girl on the bus began to sing a pop song and soon all the others_________.
A．joined
B．joined in
C．attended
D．took part in
我国的职业病防治工作原则是什么？
