A:自然选择
B:人工选择
C:自然演化
D:优胜劣汰
①Tom about me very thin three tails play with a stick
②Hello,I'm a rabbit. I'm white. My ears are long.
我国社会主义制度基本建立起来的标志是( )
计算15÷3.3商是,精确到0.01是.____