The best answer choice is A) Changing values limit interpretation.
Historians themselves are embedded in time periods and cultures, and the times and cultures in which they live influence their understanding and interpretation of the history they record. Historiography, that is, the writing of history, is a field of study in itself, seeing the work of historians within the different contexts from which they were doing their research and writing.
Answer B is incorrect because new evidence frequently becomes available. Primary sources (C) need to be read with care, because (like anything) they can be biased and unreliable in some ways. But primary sources are the material from which historians must derive their understandings of people and events. Revisionists and traditionalists each have their own interpretations, but they are part of the story of changing interpretations of history, themselves being influenced by different values that affect interpretation.
