After multiple reviews, I understand why B conflicts with information in the passage. I do not understand why answer choice D does not. I see it as, if reporting became more accurate, then there is an alternate reason for why the incidence of injuries changed between 1950-1980. Please help and let me know where the flaw in my logic is. Thanks!

Why is A wrong

I am confused here. I understand why the first part of A is correct. But, in regard to the second part of A, weren't the people who benefitted from the reforms the elites according to the passage?

I am confused on why B is correct. I originally discounted it because it says "only by discovering the chemical composition of the protoplasm... ." I did not think that the passage reflected that this is the only way, but rather that it is an important aspect. Any help is much appreciated!