A scientific team compared gold samples from several ancient artifacts with gold samples from an ancient mine in western Asia . The ratios of the trace elements in these samples were all very similar, and they were unlike the trace-element ratios from any other known mine. It is ttherefore likely that the gold in the artifacts was dug from the ancient mine. Which one of the following, if true, most weakens the argument? ['Much of the gold dug from the ancient mine in western Asia was transported to faraway destinations.', 'Ancient gold artifacts were often constructed from gold taken from earlier artifacts.', 'The ancient mine tapped into a large underground deposit that also supplied nearby riverbeds with significant quantities of gold. GO ON TO THE NEXT PAGE', 'The ancient mine was first operated many centuries before the artifacts were constructed.']