Question

Where does the production of Carbon-14 occur?

Answer 1

Carbon 14 is produced in the upper levels of the troposphere and in the stratosphere, by the action of cosmic rays on atmospheric nitrogen.

Explanation:

Carbon 14 is produced in the upper levels of the troposphere and in the stratosphere. Here atmospheric nitrogen meets up with reactive neutrons made from cosmic rays, and some of the neutrons react with the nitrogen nuclei to make carbon-14. This is an example of a cosmogenic nuclide.

Some carbon-14 was also produced by above-ground nuclear testing in the bad old days of the Cold War.

Reference: https://en.wikipedia.org/wiki/Carbon-14