Which of the Following Statements About Carbon Dating Is True

Which of the following statements about carbon dating is true?

A) Radioactive decay of ¹⁴C is balanced by its production from neutrons reacting with ¹⁴N in the upper atmosphere.
B) Dead organisms continue to exchange carbon compounds with the environment.
C) Carbon dating can be used to date organisms more than a million years old.
D) The half-life of ¹⁴C is less than 1,000 years.
E) None of the above