绿色植物从外界吸收水、无机盐和二氧化碳，通过光合作用制造出自身所需要的葡萄糖、淀粉等有机物；动物直接或间接地以植物为食，来维持生存．这说明了生物所具有的共同特征是____．

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    “Billy, one, two, three, get up! It is 25^th February, 2099, seven' o'clock．It's time to get up and go to school, ”says the clock-robot in a loud voice．Then the clothing—robot dresses(给……穿衣服)Billy quickly．Next the kitchen—robot gives Billy some bread and eggs.  Billy doesn't like them, and the kitchen—robot gives him a hamburger．After eating the hamburger, Billy goes to school．When he gets out of the house with his schoolbag, he sees a car-robot waiting for him．“Hello! I will drive you to school．Your name is Billy, isn't it?” asks the car．“Right．”Billy answers．“Now would you please show me your school ID card?” says the car．Billy shows it his school ID card．“Get in, please．”Billy gets in it．Then the car goes on, “l will check your homework today．Please take it out．”Billy does as what the ear-robot says．When they get to school, the car says to Billy, “See you tomorrow, Billy．Good luck!”

网络作家周小平的作品《请不要辜负这个时代》，洋溢着浓浓的爱国心、民族情，体现了当代青年人的责任、担当，点击量高达几千万人次。《请不要辜负这个时代》受欢迎是因为它(   )

①以正确的舆论引导人，以优秀的作品鼓舞人

②以现代传媒手段丰富了中华文化的内涵

③弘扬主旋律，坚决抵制西方各种思想的冲击

④弘扬以爱国主义为核心的中华民族精神