在特定的培养基上,培育出了纯种的酵母菌,这些酵母菌构成了一个 ( )
A:细胞
B:个体
C:种群
D:群落
在与父母的相处中,我们可以选择( )
The fire started on the second floor and it wasn't long ______ the whole building was burned down.
____ ____ people____to know the world in the past?