D. You use semi colons when you could’ve stopped the sentence but the author decided not to so both sides of the semicolon make a sentence
I find all of the answers pretty neutral (that is, giving only facts, no judgements) except on sentence 3: this is because of the word "sharply".
It seems that the author of this sentence makes a judgement about the split: that they're very split, that their argument was very intense. It seems like a judgement to me more than the other sentences.
The correct answer would be A.Plot
