While (A) does not feel particularly strong, it does provide a reason to doubt the sceptics. It seems like the validity of the upper layers is not in doubt, yet (A) would have skewed those upper layers as well.
(E) is incorrect because lack of evidence is not evidence of a lack. Just because it is the first time that something has happened does not mean that the thing itself did not happen. By the same reasoning as (E) we could say "surely neil armstrong did not walk on the moon, since nobody had ever done so before" or "surely Leeuwenhoek did not observe bacteria with a microscope, because no procedure for observing bacteria had ever been successful before. Lack of past success does not indicate lack of future success.
