for the young man to spit in the subway!A. How bad manners it isB. How bad manners they

问题补充：

for the young man to spit in the subway!

A. How bad manners it is

B. How bad manners they are

C. What bad manners they are

D. What bad manners it is

答案：

A. How bad manners it is

B. How bad manners they are

C. What bad manners they are

(答案→)D. What bad manners it is

解析：句意：年轻人在地铁里随地吐痰是多么不好的行为啊！此处因为强调名词bad manners感叹句，所以用what，句中it是形式主语，真正的主语是后面的动词不定式的复合结构for the young man to spit in the subway。