Now more and more college students are taking courses ______ a degree.
A.that led to B.led to C.leading to D.lead to

答案我知道，就是想搞清楚，但这个句子的意思模模糊糊，想知道的详细点，句意和语法。谢谢！

还有，请问有没有专门练习英语听力的网站？ 有试题最好。

C.leading to
V-ing做后置定语.可以写成从句：that lead to a degree.
一般来说是主动句，就用V-ing做后置定语；是被动句，就用过去分词做后置定语。
例如：
Do you know the girl standing by the door?(who stands by the door.)
Do you know the young man beaten by the old man?(who was beaten by the old man.)


关于听力训练嘛，在google里输入“英语听力”，会出现一堆网站，选几个看。