Question

Where does most of Earth's available carbon come from?

A. the constant process of photosynthesis

B. sunlight that is transferred from the Sun to Earth

C. the convection process that occurs in Earth's mantle

D. dead organisms that are recycled back into the environment

Answer 1

C. The convection process that occurs in Earth’s mantle. Carbon dioxide is stored deep within Earth's mantle, and rises to the surface, which comprises 2/3 of Earth's volume.

Answer 2

Answer: the constant process of photosythesis

Step-by-step explanation:

it say in the etxt book