Mr. Leslie, who _____ in Taiyuan for three years in the 1980's, is now a well-know lawyer in London. [ ]

A. has worked

B. worked

C. was working

D. would work

在加热炉燃料气调节阀开度不变的情况下，开大燃料气火嘴阀门，燃料气（）。

A.压力将不变

B.压力将变大

C.压力将下降

D.出现带液现象