在中国近现代史上，伴随中国人民的抗争、探索、建设等活动，***无疑是一盏明亮的指路明灯。随着***的成立，中国革命才迎来胜利的曙光，中华民族开始重绘曾经的辉煌。阅读下列材料，回答问题。

材料一

——北师大版八下历史课本

材料二 “……***以马克思列宁主义、***思想、邓小平理论和“三个代表”重要思想作为自己的行动指南。……” ——《***章程》

材料三“世界是多向度发展的，世界历史更不是单线式前进的。中国不能全盘照搬别国的政治制度和发展模式，否则的话不仅会水土不服，而且会带来灾难性后果。”——******在比利时布鲁日欧洲学院的演讲

下列代数式的值中，一定是正数的是（   ）

C

    I live in a beautiful city of Yunnan province. Many visitors come to my city every year.

    There are so many colorful pea­cocks(孔雀) here. Most peacocks live on the grass land of Spring Square. Some visitors give food to the birds freely. They usually throw food to them, and don't think about at all whether(是否) the food is right or not. Some of the peacocks became ill, some even died after eating the bad food from the visitors.

    I'm sure most of the visitors who throw food to the peacocks really like the birds, but don't know that they may be doing something bad to them.

    I think we should show a notice to tell the visitors that this kind of thing must be stopped. Also, we can build some small shops beside the square to sell peacock food. It's really important to give more love to these beautiful birds and to look after them carefully.