The first stable product of photosynthesis in `C_(3)` plants is :

Options

A. 3-phosphoglyceric acid
B. Dihydroxyacetone phosphate
C. Fruetose-1, 6-diphosphate
D. Ribulose-1, 5-di phosphate

Answer

### Step-by-Step Solution:

1. **Understanding C3 Plants**: C3 plants are those that utilize the Calvin cycle for photosynthesis, where carbon dioxide is fixed into a stable intermediate.

2. **Identifying the First Stable Product**: In C3 plants, the first stable product formed during photosynthesis is 3-phosphoglyceric acid (3-PGA). This compound is produced from the reaction of ribulose bisphosphate (RuBP) with carbon dioxide.

3. **Role of 3-Phosphoglyceric Acid**: 3-PGA is crucial as it is the first stable product that can be further processed to eventually form glucose and other carbohydrates.

4. **Eliminating Other Options**:
- Dihydroxyacetone phosphate (DHAP) is not the first stable product; it is derived from 1,3-bisphosphoglycerate, which is an intermediate in the Calvin cycle.
- Fructose 1,6-diphosphate is also not stable as it is a transient intermediate in the glycolytic pathway.
- Ribulose is associated with C4 plants and does not represent a stable product in C3 photosynthesis.

5. **Conclusion**: Therefore, the first stable product of photosynthesis in C3 plants is 3-phosphoglyceric acid (3-PGA).

### Final Answer:
The first stable product of photosynthesis in C3 plants is **3-phosphoglyceric acid (3-PGA)**.

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