Which of the following adds/add carbon dioxide to the carbon cycle on the planet Earth? 1. Volcanic action 2. Respiration 3. Photosynthesis 4 Decay of organic matter Select the correct answer using the code given below.
Options
(a)1 and 3 only
(b)2 only
(c)1, 2 and 4 only
(d)1, 2, 3 and 4
The full breakdown is part of the paid archive
This question's answer, explanation and links to every related question across 48 years (1979–2026) are inside the app. The two most recent years are free to read in full — no account needed.
Independent UPSC previous-year-questions study tool — not affiliated with or endorsed by the UPSC. Question text is reproduced from publicly released UPSC examination papers. UPSCviaPYQs · Privacy · Terms