代数式15ax2﹣15a与10x2+20x+10的公因式是( )
A:5(x+1)
B:5a(x+1)
C:5a(x﹣1)
D:5(x﹣1)
They were playing volleyball on the beach when it began to rain ____ (sudden).
①共性寓于个性之中,其中蕴含无数寻常父子的感情
②个性寓于共性之中,其中透着天下父亲的无私爱心
③同一性寓于斗争性,每个慈父必须面对儿子的叛逆
④斗争性寓于同一性,父子间的冲突是一种爱的冲突