题干

如图表示机体特异性免疫的部分过程示意图.下列有关叙述错误的是(  )

A:过程Ⅰ属于体液免疫,过程Ⅱ属于细胞免疫

B:吞噬细胞也参与图示免疫过程

C:细胞a只能为B淋巴细胞,细胞b只能为T淋巴细胞

D:细胞c只能为浆细胞,细胞d只能为效应T细胞

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C

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    I was at my parent's dinner table. Before me was a worn journal of thin and discolored pages. It was my grandfather's journal and now belonged to my father. My grandfather had passed away in the months leading up to my birth. I never got to visit the places he had frequently and people who had been a part of his life's journey.

    I was now about to enter his world, through the words he had left behind. Within minutes, I was attracted by the power of the written words. In the magical script before me, I was transported to another age when food was an everyday art, planned, prepared and enjoyed in the company of others, and a time when people had the heart to pause,their own lives to embrace (拥抱)each other's struggles. All this was conveyed to me in the beauty of the words that flowed together to connect with the writer's mind and understand the world they lived in.

    That kind of writing seems to be lost on us today. We have gotten used to writing in bite-sized pieces for a public looking for entertainment, and hungry for information. No wonder, there are nearly 200 million bloggers on the Internet and a new blog is created somewhere in the world every half a second. Instead of adding to our collective wisdom, most of these writings reflect the superficiality (肤浅)and impatience of our day and age.

    This not only robs us of the skill of writing impressive essays, it also prevents us from exploring what is truly important. Writing humbles us in a way that is vital for our character growth, by reminding us about the limits of the self and our appropriate place in the vast flow of life. Writing frees us by helping us explore the unknown so that we truly open up to the magic of the world around us. I saw all of this in the writing s of my grandfather. And I've seen it again and again in the writings of the greatest thinkers of humanity. Their writings reflect deep thought on issues of human importance.