To suggest that all historical narratives are equally valid is to embrace a dangerous _____, one that undermines the very possibility of objective truth and historical inquiry itself.

✓ Correct Answer: Option A

The sentence critiques the idea that all narratives are 'equally valid,' which 'undermines the possibility of objective truth.' 'Relativism' (the doctrine that knowledge, truth, and morality exist in relation to culture, society, or historical context, and are not absolute) perfectly describes this viewpoint.