红枣醋饮料中含有一种酸（C₄H₆O₅），具有美容养颜，解酒护肝健胃的重要用途。下列关于红枣醋饮料说法中正确的是（）。

根据短文理解完成下列各题。

C

    Shenzhen is a city in South China. It is not very big, but it has attracted people of the whole country and the whole world as well.

    Just about twenty years ago, it was only a small fishing village. There were not many people there. Most of them lived on fishing. Things have greatly changed since the 1980's. It became the first special economic zone (经济特区) in China.

    Because of the opening policy(政策), economic changes between China and the outside world have increased greatly. People can come and go easily between Shenzhen and Hong Kong. Both foreigners and Chinese have built a lot of factories, companies and tourists' attractions there. People all over the country have come to find jobs. Many of them have settled down in this new booming(兴起的) city.

    Shenzhen is developing so fast that it has become a well-known metropolis(大都市) in China.

 请记录下列量具所测物理量的数值．

阅读理解

　　One day, Justin decided to spend the holiday with his old friend Andrew in Australia. Their plane arrived in Sydney at ten in the morning. They had a good rest in a hotel. The next morning they rented(租)a car and began their travel. Justin found a river and they drove the car there quickly. Soon they got to the river. Before they jumped into the water, Andrew saw a boy playing under a big tree. He asked, “Are there any crocodiles(鳄鱼)in the river? ”“No, there aren’t, ”answered the boy. So they began to swim in the river. After a while, Justin felt something hit against(撞击)his leg. He told Andrew about it. They were afraid and stopped swimming. Andrew asked the boy loudly, “Is it true that there aren’t any crocodiles in the river? ”

“Yes, sir, ”said the boy, “But there are many sharks(鲨鱼)in the river. ”