Studying the decay of radioactive isotopes in dead organisms helps scientists to identify fossilized remains. The ratio of C-12 to C-14 in the atmosphere is 1 x 1012. The table shows this ratio inside the body of three organisms. C12/C14 Ratio
Organism C12/C14 Ratio
A 1 x 1012
B 2 x 1012
C 4 x 1012

What can most likely be concluded from the above information?
Only Organism A is dead, and Organism C is older than Organism B.
Only Organism A is dead, and Organism B is older than Organism C.
Both Orgamism B and Organism C are dead, but Organism C has been dead longer than Organism B.
Both Orgamism B and Organism C are dead, but Organism B has been dead longer than Organism C.

Both Organism B and Organism C are dead, but Organism C has been dead longer than Organism B.

Carbon-14 is a radioactive isotope that can decay. This isotope can be used to determine how long ago an organism died by knowing the ratio from 12C to 14C

This ratio remains constant as long as the organism is still alive, and when the organism dies, the amount of 14C in the organism begins to decay

So we can look at the amount of 14C in organism remains to determine the ratio of 12C to 14 C

The longer an organism is dead, the greater the ratio of 12C to 14C as the 14C isotope continues to decay

From the above information, can be concluded :

Organism A alive, Organism B and C have been dead

Alive : because the ratio is the same as the ratio of C-12 to C-14 in the atmosphere

The C12/C14 ratio of organism C greater than organism B, so Organism C has been dead longer than Organism B.