阅读下面短文判断句子对(√)错(×)。

      Do you like snow? I think you will say " Yes ". In winter, the weather is very cold. Many children like to

play with snow. Some of them make snowmen. They're very happy. Where does the snow come from? It

comes from little water drops. When the temperature falls below (在……以下) 0℃, the little water drops

become snow. They're white and clean, like small flowers. They make the world more beautiful.

( ) 1. The weather is very hot in winter.

( ) 2. Many children like to play with snow.

( ) 3. We can't make snowmen when it snows.

( ) 4. The snow comes from litter water drops.

( ) 5. When the temperature falls below 0℃, it begins to snow.

以下有助于细胞因子检测活性作用的是（）

A.刺激细胞增殖或集落形成的活性

B.维持细胞生长和存活的特性

C.抑制细胞生长或破坏细胞的效应

D.促进细胞趋化或抗病毒作用

E.以上都是