whose引导定语从句可以指物吗

请看下面这道题：

I saw some trees __________ leaves were black with disease.

A. its B. whose C. his D. the

事实上，用作关系代词的 whose 与 who，whom不一样，它不仅可以指人也可以指物(用作定语)：

There are some students whose questions I can’t answer. 有些学生的问题我不能回答。

Can you see the mountain whose top is covered with snow? 你看得见山顶上覆盖着雪的那座山吗?

Here is a word whose meaning escapes me. 这里有一个词，我一下想不起它是什么意思了。

■窗户破了的那座房子是空的。

正：The house whose windows are broken is empty.

正：The house the windows of which are broken is empty.

正：The house of which the windows are broken is empty.

There I saw a large table，two legs of which were broken. 在那里我看见有一张大桌子，其中有两条腿断了。