Question

choose the correct answer.
what is a consequence of humans heavily using fossil fuels in the context of the carbon cycle?
significant release of carbon dioxide
reduced pollution
lower sea levels
increased precipitation

Explanation:

When humans burn fossil fuels, carbon that was stored in the fossil fuels is released. This carbon combines with oxygen to form carbon dioxide ($CO_2$). Fossil fuel combustion is a major source of $CO_2$ emissions. Reduced pollution is incorrect as burning fossil fuels adds pollutants. Lower sea levels is wrong because melting ice (from global warming due to $CO_2$) raises sea levels. Increased precipitation is not a direct consequence related to the carbon cycle from fossil fuel use in the way $CO_2$ release is.

Answer:

significant release of carbon dioxide