Photosynthesis releases oxygen bubbles in sunlight

Steps:

• Observe bubbles from underwater plants on a sunny day, indicating active light-dependent processes.
• Recall photosynthesis equation: 6CO₂ + 6H₂O + light → C₆H₁₂O₆ + 6O₂, where oxygen gas is produced.
• Identify bubbles as O₂ released from water splitting in the light reaction.
• Confirm energy source is sunlight, enabling the process.

Why C is correct:

• Photosynthesis's light-dependent stage splits water (photolysis), releasing O₂ as a byproduct, per the equation 2H₂O → 4H⁺ + 4e⁻ + O₂.

Why the others are wrong:

• A: Photosynthesis consumes CO₂, not produces it; energy comes from light, not CO₂.
• B: Respiration releases CO₂ but occurs continuously; sunny conditions favor net O₂ production via photosynthesis.
• D: Photosynthesis energy derives from sunlight, not root-absorbed minerals, which support nutrient uptake.

Final answer: C