根据首字母提示完成短文。

     Sanya, Harbin and Beijing are three c      in China, and they are in different

places. They are quite f        from each other. Sanya is in Hainan Province and

it's in the w       place of China. Even in winter, it's about 15℃ in the  daytime.

Harbin is in the n             of China. It's cold in w        . sometimes －30℃.

There is an Ice and Snow Festival that lasts six w           . Beijing is not very

cold in winter. It's about -5℃. It doesn't o       ram or snow. The p       of hotel

rooms are quite different, too. In Beijing hotels usually cut t       prices in

winter. About 200 yuan a night is e           .

下列不存在丁达尔效应的分散系是

A．食盐水

B．稀豆浆

C．有尘埃的空气

D．向沸水中滴入FeCl₃饱和溶液所得液体