这里能用because吗?We are looking forward to the Olympic Games,___a___ they .
7 We are looking forward to the Olympic Games,___a___ they have never been held before in this country.
a.for \x05b.why \x05\x05c.because of \x05\x05d.due to
如题：a处能用because吗?为什么?还有就是they have never been held before in this country.是不是个完整及句子啊?