选a,题意是考冠词,
(1)首先 是one before所以是单数,或者从more来看,b就错,如果要选b,原句要改成more exciting matches before.
(2)a和c的区别是,c中的the是个定冠词,是指定的一个特别的match,但是句中没有这个意思,只是说以前没见过哪个比这个精彩,是个泛指,所以不能用the而要用a,如果要选c,必须指出一个具体的match比如,the match of last week was more exciting than this one .或 the match in last week was not as exciting as this one.