That tree ,__ are almost bare ,is a very old one .

问题描述:

That tree ,__ are almost bare ,is a very old one .
A branches B whose branches C its branches D the branches

选 B
这里是考察定语从句.先行词是the tree,这里的whose是所有格,相当于.的,这里是树的枝.whose branches 就是The tree's branches
其他三个选项都不成立,因为不是从句不能有几个谓语同时存在,假如选其他的话,谓语就有 are和 is,所以必须处理成从句形式.
这句话的意思是:那棵很少树枝的树是一棵老树了.