下列关于细胞中化合物及其化学键的叙述，正确的是（　　）

阅读理解

    Mary is a very little girl. She is only three years old. She can't read and write, but she likes drawing very much.

    One day, her sister, Jean sees her at the desk. She thinks Mary is drawing. She comes to her, but she finds Mary isn’t drawing. She is writing on the paper.

“What are you doing, Mary?” Jean asks her.

“I’m writing to Ann. ” She answers.

“But you don’t know how to write, how can you write to her?”

“Oh, it doesn’t matter(没关系). Ann can’t read and write, either(也). ”

阅读图文资料，完成下列要求。

西班牙是欧洲发达国家中发展水平相对较低的国家。西班牙阿尔梅里亚省(位置见图a)的甲地附近干旱少雨。1956年当地勘探到深层地下水后，灌溉农业得到发展。1971年引入滴灌技术，日光温室（不需人工增温）快速普及，生产的蔬菜、瓜果等农产品出口量大增，主要出口西班牙以北的欧洲发达国家。20世纪90年代以后，甲地温室农业进入集温室安装维护、良种培育与供应、产品销售、物流等为一体的集群式发展阶段，产品出口量加速增长。图b示意甲地最低气温和降水量的年内变化。