I think that the answer might either be C or B
In the story "An Unlikely Heroine" by Elizabeth Kibler, Alisa also makes the happy outcome of the story possible by encouraging Teresa to stay on the team until the end of the season. Had Alisa not done that, Teresa would not have been able to step in to coach the team in the critical moment of the story.
It's not a simple sentence: it has more than one clause.
It is also not compound: the two clauses are not independent <span>and a compound has independent clauses.
</span>It is however complex: the two clauses are not independent (<span>While you were on vacation is the dependent clause). This is the correct answer.
(it's not compound-complex because it has 2 and not more clauses)
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