What is the main purpose of the carbon cycle?

The main purpose of the carbon cycle is to recycle carbon among different Earth systems. This cycle involves continuous movement of carbon through the atmosphere, biosphere, hydrosphere, and geosphere. It plays a critical role in regulating Earth's climate and supporting life, as carbon is a fundamental element found in all living organisms and is an essential component of various geological and chemical processes.

In the carbon cycle, carbon is stored in various forms—such as carbon dioxide, organic matter, and fossil fuels—and is released back into the environment through processes like respiration, decomposition, and combustion. The interactions among plants, animals, and the atmosphere facilitate the transfer of carbon, allowing it to be reused within ecosystems and maintaining the balance necessary for life.

This recycling aspect emphasizes the connectivity between living and non-living components of Earth, demonstrating how carbon is essential for sustaining life while influencing geological processes over long timescales. The other options do not capture the comprehensive function of the carbon cycle, as they either focus on specific outcomes or limitations rather than the overall process of recycling carbon continuously.