Travelling by plane is _____ expensive.       [ ]

A. much more

B. more much

C. too much

D. much too

下列与晚发型矽肺发生有关的条件中，哪项是错误的（）

A.作业工人体质比较虚弱

B.接触的粉尘浓度较高

C.粉尘中游离SiO₂含量高

D.接触粉尘年限较短

E.脱尘时X线胸片未见明显异常