Is all of Earth's carbon dioxide supply constantly being used by organisms?

Question

a. yes, and it is used up as soon as it is formed
b. no, some is stored in Earth's only carbon sink, such as the oceans
c. no, some is stored in Earth's carbon sinks, such as the oceans
d. yes, and it briefly passes through the atmosphere as it cycles between organisms

Answer 1

The correct answer is:

c. no, some is stored in Earth's carbon sinks, such as the oceans

While organisms do use carbon dioxide for processes such as photosynthesis, a significant amount of carbon dioxide is stored in carbon sinks like the oceans, forests, and soil, rather than being constantly utilized by organisms.