阅读下面文段，回答后面问题。
         小草偷偷地从土里钻出来，嫩嫩的，绿绿的。园子里，田野里，瞧去一大片一大片满是的。坐着，躺着，打两个滚，踢几脚球，赛几趟跑，捉几回迷藏。风轻悄悄的，草软绵绵的。
         桃树、杏树、梨树，你不让我，我不让你，都开满了花赶趟儿。红的像火，粉的像霞，白的像雪。花里带着甜味儿；闭了眼，村上仿佛已经满是桃儿、杏儿、梨儿。花下成千成百的蜜蜂嗡嗡地闹着，大小的蝴蝶飞来飞去。野花遍地是：杂样儿，有名字的，没名字的，散在草丛里像眼睛，像星星，还眨呀眨的。

    In our town, there is a big zoo with a lot of animals in it. There are so beautiful tigers and two old lions. They eat a lot of meat every day.
There are also two big elephants and one baby elephant. The elephants are kind animals. They eat a lot every day. They like children. Children often give them bread and bananas. Elephants like bananas best.
    In our zoo there are also brown bears, black bears and white bears. They stand on their hind legs, hold up their four legs and ask for food. They like cakes very much.
    There's also a children's corner in our zoo. Children ride horses and donkeys and watch the monkeys there. The monkeys are very funny. They climb up ropes and jump down again and play with each other like small children.

长江源头姜根迪如冰川、尕恰迪如冰川面积不断缩小。以上现象反映了（　）

下列几个不同进制数最大的是（　　）