Hi,
This is a short passage. What Ron mentioned about change applies to long passages. If you follow his methodology, this is what you should be reading in the passage to ascertain the main idea:
-The dominant view in recent decades......
-Another view claims......
-More recent fieldwork, however, has shown.....
-In short, there are now strong reasons to think that it was erroneous to claim .......
As you can see from the above that his main idea was to present a new perspective, which contradicts the older views. Even if you were stuck between C and D, D is completely opposite. He is not defending the traditional views, but in fact stating that those claims were not correct.
Hope this helps
Regards
Sunil