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單項選擇題

【A1型題】The purpose of the ashing step in graphite-furnace atomic-absorption spec-troscopy is to()

A.Vaporize metal atoms to be analyzed
B.Cause the metal species to form carbides which are more volatile
C.Convert the graphite furnace to ash to avoid carbide formation
D.Burn off organic species that would interfere with the elemental analysis

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