Questions: Which best lists the end products of the light-dependent reactions of photosynthesis? ATP and NADPH CO2 and H2O ATP, NADPH, and O2 C6H12O6 and O2

The answer is the third one: ATP, NADPH, and $\mathrm{O}_{2}$.

Explanation for each option:

1. ATP and NADPH: This option is partially correct as ATP and NADPH are indeed products of the light-dependent reactions, but it is missing $\mathrm{O}_{2}$.
2. $\mathrm{CO}_{2}$ and $\mathrm{H}_{2} \mathrm{O}$: This option is incorrect because $\mathrm{CO}_{2}$ is used in the Calvin cycle (light-independent reactions), and $\mathrm{H}_{2} \mathrm{O}$ is a reactant in the light-dependent reactions, not a product.
3. ATP, NADPH, and $\mathrm{O}_{2}$: This option is correct. The light-dependent reactions of photosynthesis produce ATP and NADPH, which are used in the Calvin cycle, and $\mathrm{O}_{2}$, which is released as a byproduct.
4. $\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}$ and $\mathrm{O}_{2}$: This option is incorrect because $\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{6}$ (glucose) is produced in the Calvin cycle, not in the light-dependent reactions.

Summary: The end products of the light-dependent reactions of photosynthesis are ATP, NADPH, and $\mathrm{O}_{2}$.