— Are these your books?—No, they aren't. They're___

试题详情及答案解析: — Are these your books?
—No, they aren't. They're____.
A. her B. his C. mine; 答案：B; 试题分析：句意：--这些是你的书吗？--不，不是。这些书是他的。名词性物主代词=形容词性物主代词+名词。只有上文提及了某个名词，才会知道名词性物主代词指代的事物。后面是名词的话，前面就要用形容词性物主代词。后面没有名词的话，就用名词性物主代词。结合句意，故选B。
考点：考查代词的用法。