Final answer:
The process of H2O splitting in the thylakoid space is known as photosynthesis.
Step-by-step explanation:
The process of H2O splitting in the thylakoid space is known as photosynthesis.
During photosynthesis, water molecules are split into oxygen (O2), hydrogen ions (H+), and electrons in the thylakoid space. This splitting of water releases oxygen and generates the energy required for the production of ATP and NADPH, which are used in the subsequent reactions of photosynthesis.
Therefore, the correct answer to your question is A. Photosynthesis.