阅读下列短文，从每题所给的四个选项（A、B、C和D）中选出最佳选项。

    Four seasons make a year. They a re spring, summer, autumn and winter. 

    Spring is a beautiful season. It's from March to May. In spring, trees turn green and flowers come out. Everything looks new.

    Summer is a happy season. It's from June to August. The weather is hot, so people usually wear cool clothes, go swimming and eat ice cream.

    Autumn is a colourful season. It is from September to November. In autumn, leaves on trees turn yellow. Sometimes they are yellow and red. The colours are beautiful.

    Winter is the last season. It's from December to February. In China, the weather is not the same in winter. In Beijing, it's very cold. It often snows. People often play with snow and go skating in rivers and lakes. Skating is their favorite sport in winter. But in Haihan, it's not very cold. It's very warm. People there can go swimming in the sea.

材料一：“丝绸之路经济带”是在古丝绸之路概念基础上提出的一个新的经济发展战略。新疆处于古丝路北、中、南三条大道交汇之地，成为新丝路上的核心区。

新疆具有地理区位优势，与8个国家接壤、东联内地、西通欧亚。资源优势，石油天然气、煤炭及各类矿产资源丰富。而且是通往中亚的国际能源资源通道。历史文化优势，新疆是东西方文化的交汇点，形成了独特的地域文化和民族文化。政策优势，19省市对口支援、国家财税、金融、产业政策优惠。

材料二：文化是贸易交流合作的第一壁垒，文化交流对贸易发展起着至关重要的作用。“新丝绸之路经济带”发展首先要解决的是和亚欧文化的交融问题，为经济发展打开第一道壁垒。

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