She was just about to explain _________ she hadn't passed her maths test chiefly out of carelessness _________ her uncle came.
B、to her mother why；that
C、her mother that；when
D、to her mother that；when
explain/announce等后面的结构是～ sth．to sb．或～ to sb．sth．，to 不可省略。
—Have you heard the latest news？
—The last one ________ pays the meal.
We _________ so as not to wake the roommates.
Some pre school children go to a day care center，_________ they learn simple games and songs.
_________ nothing more to discuss，the CEO got to his feet，said goodbye and left the meeting room.
D、As there being