He stood up ( ) he could see the words on the blackboard cle

答案：C
A不对,such是形容词,它所修饰的名词可以是可数名词,也可以是不可数名词；名词前面可以带形容词,也可以不带.如果其后是单数可数名词,前面需加不定冠词a或an.
B不对,没有so as that 这样的搭配,只有so as to 意思是“以便.”
D不对,in order to 才是正确的搭配,表示“目的是,为了.”