题干

美国科学家鲁宾和卡门利用同位素标记法对光合作用进行了研究,他们利用18O分别标记CO2和H2O,使它们分别成为C18O2和H218O,通过分组试验追踪18O在化学反应中的去向.关于该实验结果的相关叙述正确的是(    )

A:H218O的标记元素会出现在O2

B:证明了C18O2中的标记元素进入有机物中

C:C18O2中的标记元素进入了O2

D:该实验研究的是暗反应过程中物质变化

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A

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    When I found out I was moving to India, it was beyond a nightmare. It was something I couldn't even imagine. The impression I had of India were only based upon a few summer visits to my grandparents, filled with heat, pollution and dirt. Even though I was only six years old, I know this would be a complete change from my comfortable life in Maryland.

    During my first six months in India, my expectations were met almost exactly. I hated my new apartment; I missed my school and friends back in Maryland, and I was sick of all the dirty marketplaces that filled the streets of New Delhi.

    After those six months were over I finally realized that I was going to be in India for a while. I knew that I had to start making the most of my new life. It was then that I became completely involved in my school. My school, the American Embassy School, was filled with international students: Europeans, Australians, Chinese, and Americans just like me. But they all welcomed me with open arms. It was amazing to be among such diverse students, who had such incredible experiences to share.

    Now, when I look back at my time in India, all I can think about is how fortunate I am to have had such a wonderful experience. My move to India not only allowed me to see a completely different side of the world, but I was also able to establish unbreakable bonds with so many interesting and amazing people. Even now, after quite some years, I am still in contact with my closest friends from the American Embassy School. I cannot even imagine what I would be like without having lived in India. I would have missed out on meeting so many extraordinary people, and I would be a completely different person today.