The sentence is correct as written. When a semi-colon is present, the clause on either side of the punctuation mark must be a complete sentence.

Choice (B) changes the meaning, suggesting that the earlier scholars did the clarification. (C)'s use of "that" before "repeats" is incorrect; the phrase following "that" is merely a description, so "which" would be more appropriate. (In fact, neither is needed, as shown in (A).)

Choice (D) uses two semi-colons; the middle clause is not a complete sentence. Finally, (E) contains a passive construction ("are repeated by it") which might be acceptable if there were no better options, but since (A) is a strong choice, there's no need to select this one. Choice (A) is correct.