I will ask my parents______________分析一下句子成分

题目

I will ask my parents______________分析一下句子成分
A whether they will agree to go
B if they let me go
C if they will let me go
D whether they allow me to

答案

主句将来时 宾语从句用一般现在时 排除AC
D应为whether they allow me to go or not
故选C