英语 啊啊啊啊啊啊 啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊 嗷嗷 啊

不可以。for which 此处不是”为什么，因为...原因“， 所以不能改为why
但是这个句子本身是错的。
老师才能“give。。exam”，学生只能“take the exam/ sit in for the exam";如果是没有得到成绩，应该是did not get the score;
happen不及物动词，不能用过去分词形式修饰名词，而because of后面不能跟从句，happened又不能被看作从句谓语。take responsibility for，不用up
所以句子应该是
A student did not get his score for the exam because of the mistake made by the test center, who refused to take the responsibility.
或：....， but it /they would not take
it /they refused to take...

不可以 这句里有个定语从句里面which指的就是the mistake
这句话可拆为：
A student didn't give his exam(事实) because of the mistake which happened in the test.(直接原因)
They(指考试中心) don't want to take up the responsibility for the mistake.（这句话解释这个失误）

不可以