Please help!

Hi- the passage sets up a contradiction. The writers who theorized feudalism assumed the existence of a noble class, which required heritability. However, heritability did not appear until feudalism was in decline. From this, we know that the original theorists were wrong about feudalism requiring a noble class. This is a decent match for A. While the part about it distorting history is a bit stronger than I expected, it is supposed by the passage.