Final answer:
Water (A) is a molecule that is split to replenish the electrons and also produces oxygen gas during photosynthesis.
Step-by-step explanation:
The molecule that is split to replenish the electrons and also produces oxygen gas is water (A).
During the process of photosynthesis, water is split in a process called photolysis. This splitting of water releases electrons, which are then used in the light-dependent reactions of photosynthesis to generate energy-rich molecules like ATP. Oxygen gas is produced as a byproduct of this process.
For example, the overall reaction for photosynthesis is:
6CO₂ + 6H₂O + Light energy -> C₆H₁₂O₆ + 6O₂
This shows that water (H₂O) is a necessary component in the production of oxygen (O₂) during photosynthesis.