Identifying Processes in the Carbon Cycle

Steps:

• Recognize X as the process that absorbs CO2 from the atmosphere to form organic compounds.
• Identify Y as a process that releases CO2 through burning of fossil fuels or organic matter.
• Determine Z as the process where organisms break down food, releasing CO2 as a byproduct.
• Match these to the cycle where photosynthesis sequesters carbon, while combustion and respiration return it to the air.

Why C is correct:

• Photosynthesis (X) converts CO2 into glucose via 6CO2 + 6H2O → C6H12O6 + 6O2, while combustion (Y) and respiration (Z) release CO2, balancing the carbon cycle.

Why the others are wrong:

• A: Ingestion moves matter but doesn't directly involve CO2 exchange.
• B: Ingestion isn't a CO2-releasing process like combustion or respiration.
• D: Duplicate of C, but listed as incorrect per given answer.

Final answer: C