根据史书记载，西周初年的国家有800多个，到了春秋初年，还剩下170多个，战国之初，只有十几个了，这反映了历史发展的趋势是 ( )
A：诸侯国割据混战日益扩大
B：人民遭受的灾难更重
C：封建制度正逐步确立
D：历史向统一的方向发展
During holidays，Kitty usually goes to see the exhibits in many museums，such as the history museum，the art museum，the museum of science and technology and the museum of natural history．There are thousands of wonderful things in museum.There are paintings，sculptures(雕塑)，costumes(服饰)，swords(剑)，ancient animal bones and plants，stuffed animals(动物标本)and many others．It is always a good review of history to visit those museums．It is also a great way to learn more things by myself．
