The patient,( )how serious his illness was,still refused an operation．A．not realize \x05\x05B．not to realise \x05C．not realising \x05\x05D．not being realized选哪一个,为什么?

The patient,( )how serious his illness was,still refused an operation．
A．not realize \x05\x05B．not to realise \x05
C．not realising \x05\x05D．not being realized
选哪一个,为什么?

C 句子结构可以唤作如下
The patient still refused an operation,not realizing how serious his illness was.
首先排除A和D,这句话中不缺乏谓语（refused）,所以不能用A ;意识是个人所拥有的主动形式,没有必要用被动,排除D
然后是句子结构,not realizing how serious his illness was作主语(He)的修饰状语从句,这里是从句结构,不能用不定式,排除B

c