阅读下面短文，然后从所给的四个选项中选出一个最佳答案。

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    Reading            Step 1: Identify

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    TalkEnglish.com developed the "Click, Listen, and Repeat" functionality(功能). In most of the lessons, you read the sentence, click on the sentence to listen to the sentence, and then you can practice speaking by repeating after the audio file(音频文件) provided by a native English speaker. This method improves your reading, speaking, and listening all at the same time and makes learning English easy. You will improve your English speaking using this method.

已知点P（﹣1，2），点P关于x轴的对称点为P₁，关于直线y=﹣1的对称点为P₂，关于直线y=3的对称点为P₃，关于直线y=a的对称点为P₄，分别写出P₁，P₂，P₃，P₄的坐标，从中你发现了什么规律呢？

下列属于动物的先天性行为的是（   ）

关汉卿，____末____初大都人，____家，号____。与____、白朴、____齐名，并称为“元曲四大家”。1956年被列入“世界文化名人”之列。代表作除《窦娥冤》外，还有《望江亭》____《单刀会》等。