Question

Use a comma to separate the dependent clause from the independent clause only if the subordinating conjunction _______________ the sentence.

Fill in the gap.

Answer 1

Is there any answer choices that we have to pick from?

Answer 2

No-

Answer 3

"...if the subordinating conjunction completes the sentence," maybe?
I mean, it sounds like it makes sense, but doesn't a conjunction always complete a sentence? I'm not sure, but that answer might be worth a try unless we can think of something more fitting