三道英语题1.Go and get your coat.It's____your left it.A there B w

三道英语题
1.Go and get your coat.It's____your left it.
A there B where C there where D where there
答案选B.
为什么不能选C,我的理解是it’s there是一个完整的句子,where引导定语从句.
解释一下为什么我的理解是错误的.
2.It looks like the weather is changing for ____.Shall we stick to our plan?
A the worse B worse C the worst D worst
为什么选A,我选的是B
3.china is worth travelling because it is ____most beautiful country in the world
A a B the
为什么选A