Final answer:
The electrochemical gradient during photosynthesis is formed by the movement of protons (H+), which is primarily generated by the light reactions. ATP and NADPH contribute to the formation of this gradient.
Step-by-step explanation:
The electrochemical gradient formed during photosynthesis is primarily generated by the movement of protons (H+).
During the light reactions of photosynthesis, energy from sunlight is used to drive the transfer of electrons through an electron transport chain. This chain pumps protons across the thylakoid membrane, creating a concentration gradient. This gradient can be used to power the synthesis of ATP, which is an energy carrier, and NADPH, which is a reducing agent.
Therefore, the correct answer is ATP and NADPH (options 1 and 2) as they contribute to the formation of the electrochemical gradient during photosynthesis.