C) According to the original argument, "good and bad are subjective, and thus, they always represent opinion and cannot be fact," and because my opinion is that World War II is a bad thing, the historical event called World War II (the deaths of millions) being a bad thing is an opinion, and not a fact.
D) Because my opinion is that World War II was a bad thing, and because opinions only represent subjectivity and not fact, the historical event called World War II is subjective and not a fact.
But that is not. The part of "WW2 was bad" that is opinion is "was bad" not "WW2". WW2 is not part of the original syllogism, no noun was, merely an adjective. So WW2 is fact, your description of it is opinion. At least, that's the common assertion; I think there are things that objectively worse than other things that other people will try and claim as opinion, confusing as they do quality with personal taste, but whatever. Glad I could help.
"The black wind howls. One among you will shortly perish" Magus