材料二：1870年以后，科学开始了更加重要的作用，渐渐地，它成为所有大工业生产的一个组成部分。
在一个生态系统中，“蘑菇”通常属于（ ）
Hi, I'm Huanhuan. I'm from Canada. This is my friend, Amy. She's from USA. Today we go to the zoo. We see many animals. We are very happy. I like pandas. They are fat and cute. Amy likes elephants. They have long nose and big ears. Look at the lion, he is eating meat!
选择正确的答案填在括号里。
正常情况下在用显微镜观察时，眼睛和镜筒的相关位置应该是如图的（ ）
