题干

生物大分子在生物体的生命活动中具有重要的作用。碳原子本身的化学性质,使它能够通过化学键连接成链或环,从而形成各种生物大分子。可以说,地球上 的生命是在碳元素的基础上建立起来的。以上事实可以说明(    )

A:C元素能组成各种各样的化合物

B:C元素是最基本的元素

C:C元素是各种大分子中含量最多的元素

D:C元素比其他元素重要

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答案(点此获取答案解析)

B

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    It was one of the hottest days of the dry season.  If we didn't see any rain soon, we would lose everything.
One day when I was in the kitchen, I saw my six-year-old son, Billy, walking towards the forest. He was clearly trying to be as still as possible.   Several minutes after, he had gone into the forest, he ran out again, towards. the house.  This activity went on for an hour, walking carefully to the forest and running back to the house.  I really wanted to know what Billy was doing.
    Finally I followed him into the forest.  I found that he was holding a cup of water. He walked very carefully not to drop the water.
I saw a baby deer lying on the ground.  It lifted its head to drink the water in my son's cup.  After the deer drank up, Billy jumped up and ran back to the house to get more water.  When he saw me, he said, "I'm not wasting. " I found that his eyes were filled with tears.
    “I know. " I watched the most beautiful heart working so hard to save another life.Tears ran down my face.  As my tear drops began to hit the ground, other drops and more drops and more suddenly joined them   I looked up at the sky.   It was raining.
    Some people would say this was all just a huge coincidence  (巧合).   Those miracles(奇迹)  don't really exist (存在).  I would like to believe it was a miracle.   All I can say is that the rain that came that day saved our farm just like the actions of one little boy saved a life.