The third option is correct because the error in this sentence is one of subject-verb agreement. The subject in the sentence is ‘something’, which is singular, and so ‘has’should have been used here. The confusion arises because of the plural ‘reports’, but this is not the subject of the sentence; this word is merely a noun, being used here as the object of the preposition ábout’. The object of a preposition is never the subject of the sentence. The reports, however, become the subject of the next (dependent) clause, so the pronoun ‘they’ is used to refer to the reports.
For the answer to the question above, before the competition makes sure she knows her content and topic if she finds it hard tell her to write small notes on it to expand and talk about in more detail or research it the night before the debate.