C
work 是不可数名词,所以前面不能用冠词。
如果选A的话,那么句子应该改成:How interesting the work is!
D. What an. 固定用法。
What an interesting work it is !
如。What an interesting person he is. What an interesting drwaing that is.
a
what修饰名词,正确句子是what
an
interesting
work
!,此处how修饰形容词interesting