Question

Which carbon cycle process takes decades (vs days, months or hundreds of years) to finish? (1 point)

Decomposition of organic matter on the surface.

Circulation of carbon throughout the deep ocean.

Combustion of fossil fuels for human energy use.

Plants taking in carbon through photosynthesis.

Answer 1

Decomposition of organic matter on the surface.

Reason: Surface decomposition of plant/animal material commonly takes years to decades, whereas photosynthesis is days–months, combustion is essentially instantaneous, and deep-ocean carbon circulation is on the order of hundreds to thousands of years.