What is the Largest Carbon Reservoir on Earth

Question

What is the largest carbon reservoir on Earth?
A) terrestrial biosphere
B) rocks and sediments
C) aquatic biosphere
D) fossil fuels

Accepted Answer

Rocks and sediments hold the largest carbon reservoir on Earth, containing approximately 99.5% of all carbon found in the Earth's crust. This carbon is slowly released through geological processes such as weathering and volcanic activity, and can also be stored for millions of years in carbon-rich rocks such as coal and oil shale. The other options (A, C, and D) are significant carbon reservoirs as well, but are much smaller in comparison to rocks and sediments.