下列四个选项中，平均速度最大的是（　　）

阅读短文，下列问题

Why do children like watching TV?

       Many children like watching TV. It's very interesting and they can see a lot and know many things about other people. They can learn from the radio, too. But they can learn easily from TV. Why? Because they can hear and watch at the same time. But they can't watch anything from the radio.

    TV helps to open children's mind. They can find better way to do things.

    Many children watch TV only on Saturday and Sunday evenings.They are very busy. But some children watch TV every night. They go to bed late. It's not good for their eyes and health.

美国当地时间2016年2月11日上午10点30分，美国国家科学基金会（NSF）在华盛顿特区国家媒体中心宣布：人类首次直接探测到了引力波。引力波像其它的波一样，携带着能量和信息，能够让我们回望宇宙大爆炸最初瞬间，检验宇宙大爆炸理论的正确与否。这说明（  ）

①思维与存在具有同一性             

②人们可利用客观规律为人类造福

③辩证否定的实质是扬弃             

④发展就是事物自身的运动和变化