The Current Sourcing Method Used to Fingerprint Obsidian, and Used

Multiple Choice

The current sourcing method used to fingerprint obsidian, and used by Richard Hughes to verify James Griffin's determination that obsidian in the Ohio Hopewell mounds had come from Obsidian Cliff in Yellowstone National Park some 2400 kilometers away is:

A) instrumental neutron activation analysis (INAA) .
B) petrographic analysis.
C) microscopic observation of thin sections.
D) x-ray fluorescence (XRF) .