Carbon - 14 is used to determine the age of organic material . The procedure is based on the formation of `""^(14) C` by neutron capture in the atmosphere . `T_(1) - T_(2) = (1)/(lambda) "log" (C_(1))/(C_(2))`
`""^(14) C` is absorbed by living organisms during photosynthesis . The `""^(14) C` content is constant in living organism once the plant or animal dies , the uptake of carbon dioxide by it increases and the level of `""^(14) C` in the dead being falls due to the decay which `C^(14)` undergoes .
`""_(6)^(14) C to ""_(7)^(14) N + beta^(-) (""_(-1)^(0)e)` . The half- life period of `""^(14) C` is 5770 years . The decay constant `(lambda)` can be calculated using the formula `lambda = (0.693)/(t_(1//2))`.
The comparison of the `b^(-)` activity of the dead matter with that of the carbon still in circulation enables measurement of the period of the isolation of the material from the living cycle . the method , however , ceases to be accurate over period longer than 30,000 years . The proportion of `""^(14) C` to `""^(12) C` in living matter is `1 : 10^(2)`
Which of the following options is correct ?

Options

A. In living organisms , circulation of `""^(14) C` from atmosphere is high so the carbon content is constant in organism
B. Carbon dating can be used to find out the age of earth crust of rocks
C. Radioactive material absorption is equal to its rate of decay , hence the carbon content remains constant in living organism.
D. Carbon dating cannot be used to determine concentration of `""^(14) C` in dead being .

Answer

C

Explanation

living organism `((C^(14))/(C^(12)))` is maintained as constant volume .