Why not C?

Could you please explain the correct answer? Thanks!

@joshuavt, this question is asking for which of the following does NOT fit within the author's definition of "traditional sources" as used in line 1. The author specifically states that "traditional sources" are "archeological remains and surviving texts." So when you look at the answer choices, you need to determine which of the five is NOT an "archeological remain" or a "surviving text." (A) is an archeological remain, even if the author says it's not helpful. (Wrong) (B) is an archeological remain, even if archeologists tend to discard them. (Wrong) (C) is an archeological remain. (Wrong) (D) is a reconstruction and therefore is neither a surviving text or an archeological remain. (Right) (E) is a surviving text. (Wrong) Does that answer your question?

Thanks that really helped me out! I think I was getting confused with the fact that the the remains were either discarded or labeled as not helpful. Thanks!