I am afraid I won’t have any influence over my 18-year-old daughter ______ her mind is made up.

I am afraid I won’t have any influence over my 18-year-old daughter ______ her mind is made up.
选C，解释为只要
A解释为当....
B解释为一...就...
D解释为自从...
从句意上看AC都可以，但A的时态不是主将从现，所以只能选C
有不会的可以再问我

C. once
一旦十八岁的女儿拿定了主意，恐怕我无法影响她改变她的决定。

D。自从，因为
我想我对我18岁的女儿不能施加什么影响力了，因为她已经有了自己的想法。

C is the right answer.
A : At the moment her mind is made up, I don't have any influence over my 18-year-old daught.
Or: At the moment her mind was made up, I didn't have any influence over my 18-year-old daught.
B Without " I'm afraid", we can use .