题目分式1a+1+1a(a+1)\dfrac{1}{a+1}+\dfrac{1}{a\left(a+1\right)}a+11+a(a+1)1的计算结果是（ ）A.1a+1\dfrac{1}{a+1}a+11B.a+1a\dfrac{a+1}{a}aa+1C.aa+1\dfrac{a}{a+1}a+1aD.1a\dfrac{1}{a}a1知识点：分式的乘除法章节：第18章 分式 / 18.2 分式的乘法与除法
