What Assumption Must Be True for Radiocarbon (¹⁴C)dating to Be

Multiple Choice

What assumption must be true for radiocarbon (¹⁴C) dating to be useful?

A) (¹⁴C) has the same mass as ¹²C.
B) A constant concentration of ¹⁴C is maintained in living plants and animals through equilibration with atmospheric levels of ¹⁴C.
C) The sample cannot have been chemically altered prior to the analysis.
D) (¹⁴C) always decays at the same rate.
E) (¹⁴C) is nonradioactive.