My biggest problem is ___I am too busy.I al_ways have too much to do every day.A which B when

问题描述:

My biggest problem is ___I am too busy.I al_ways have too much to do every day.A which B when
C what D that
这是跟上面连在一起的

应该选D.
因为后面是一个完整的句子,可以做从句.
所以应该填that,意思是:
我最大的问题就是我太忙了.