题干

昆虫的保护色越来越逼真,它们的天敌的视觉也越来越发达,结果双方都没有取得明显的优势,这说明()

A:自然选择不起作用

B:生物为生存而进化

C:双方在斗争中不分胜负

D:双方相互选择,共同进化

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答案(点此获取答案解析)

D

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       A man may usually be known by the books he reads as well as by the company he keeps.One should always live in the best company,whether it is of books or of men.

       A good book may be among the best of friends.It is the most patient and cheerful of companions.It always receives us with the same kindness,amusing and instructing us in youth, and comforting us in age.

       Men often discover their similarity to each other by the common love they have for a book just as two people sometimes discover a friend by the admiration which both entertain for a third.There is an old proverb,“Love me,love my dog.” But there is more wisdom in this:“Love me,love my book.” The book is a truer and higher bond (纽带) of union.Men can think,feel,and sympathize with each other through their favorite author.They_live_in_him_togetherand_he_in_them.

       A good book is often the best container of a life preserving the best that life could think out,for the world of a man’s life is,for the most part,the world of his thoughts.Thus the best books are treasures of good words and the golden thoughts,which become our steady companions and comforters.

       Books are by far the most lasting products of human effort.Temples and statues decay (腐朽),but good books survive.Time is of no account with great thoughts,which are as fresh today as when they first passed through their author’s minds ages ago.

     The great and good do not die,even in this world.Preserved in books,their spirits walked abroad.The book is a living voice.It is an intellect (智者) to which one still listens.