下图反映某生理过程或现象，以下叙述不正确的是 

A．若x表示家庭酿造葡萄酒时的温度变化，则曲线表示产酒量与温度变化的关系

B．若y表示饭后血液中葡萄糖含量变化，则BC段曲线是由于胰岛素的作用，血液中部分葡萄糖转化为糖原

C．在草→兔→狼的封闭草原生态系统中，若大量捕杀狼群，曲线表示一定时间内兔的数量变化

D．曲线表示菜豆种子在萌发成幼苗的过程中有机物含量的变化情况

This is a famous street in China. What is it It’s West Street. Why is it so famous Now let me tell you something (41) it.
West Street is in Yangshuo, Guangxi. It’s over 1,400 years (42) .It’s about 1,000 meters (43) . But it’s very clean and beautiful. In the street, there are (44) shops. The things in the shops are nice and cheap. Every day, lots of visitors come here. Many of (45) are foreigners. It’s a good place to practice speaking English. So West Street is called the biggest English corner. Some people (46) call it the earth village. Almost everyone in the street (47) English.
But you mustn’t ride your bike or drive your car in the West Street. You can only (48) here. Why Because it’s a walking street. In the street, you needn’t worry that you’ll be hit by cars. (49) happy!
West Street is a wonderful place to visit. (50) West Street.

[A] they [B] them [C] their