Question

carbon is eventually returned to the atmosphere through which of the following? choose one option a cellular respiration b photosynthesis c dna replication d cell division

Explanation:

To determine how carbon is returned to the atmosphere, we analyze each option:

• Option A: Cellular respiration is the process by which cells break down organic molecules (containing carbon) to release energy, and in the process, carbon dioxide ($\ce{CO_2}$) is produced and released into the atmosphere.
• Option B: Photosynthesis is the process by which plants take in $\ce{CO_2}$ from the atmosphere and convert it into organic compounds, so it removes carbon from the atmosphere, not returns it.
• Option C: DNA replication is the process of copying DNA, which is related to genetic material duplication and does not involve the release of carbon into the atmosphere.
• Option D: Cell division is the process of a cell dividing into two daughter cells, which is about cell growth and reproduction and does not directly involve returning carbon to the atmosphere.

So, the correct option is A as cellular respiration releases carbon - containing $\ce{CO_2}$ back to the atmosphere.

Answer:

A. Cellular respiration