During light reaction in photosynthesis the following are formed.

Options

A. ATP and sugar
B. hydrogen, `O_(2)` and sugar
C. ATP, hydrogen donor and `O_(2)`
D. ATP, hydrogen and `O_(2)` donor

Explanation

**Step-by-Step Solution:**

1. **Understanding Light Reactions**: The light reactions of photosynthesis occur in the thylakoid membranes of chloroplasts and require sunlight. They convert solar energy into chemical energy.

2. **Key Products of Light Reactions**: The main products formed during the light reactions are:
- **ATP (Adenosine Triphosphate)**: This is produced through photophosphorylation.
- **NADPH (Nicotinamide Adenine Dinucleotide Phosphate)**: This acts as a reducing agent and is produced when NADP+ accepts electrons and protons.
- **Oxygen (O2)**: This is released as a byproduct from the splitting of water molecules (photolysis).

3. **Analyzing the Options**:
- **Option 1**: ATP and sugar - Incorrect, as sugar is produced in the Calvin cycle (dark reactions), not in light reactions.
- **Option 2**: Hydrogen or O2 and sugar - Incorrect, as hydrogen is not a product; rather, NADPH acts as a hydrogen donor.
- **Option 3**: ATP, hydrogen donor (NADPH), and O2 - Correct, as ATP and NADPH are produced, and O2 is released.
- **Option 4**: ATP, hydrogen, and O2 donor - Incorrect, as hydrogen is not produced; NADPH is the hydrogen donor.

4. **Conclusion**: The correct answer is **Option 3**: ATP, hydrogen donor (NADPH), and O2.