The structure of flower which forms pericarp in true fruit is

Options

A. Thalamus
B. Outer integument of ovule
C. Stalk
D. Wall of ovary

Answer

To solve the question regarding the structure of a flower that forms the pericarp in a true fruit, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Pericarp**:
- The pericarp is the outer portion of the fruit. It serves as the protective layer surrounding the seeds.

2. **Identifying the Source of Pericarp**:
- The pericarp is specifically formed from the wall of the ovary of the flower. When a flower undergoes the process of fertilization, the ovary develops into the fruit.

3. **Role of Ovary in Fruit Formation**:
- As the flower transitions into a fruit, the ovary wall thickens and matures into the pericarp, which encases the seeds that develop from the ovules within the ovary.

4. **Differentiating Other Structures**:
- While other structures like the thalamus, outer integument of the ovule, and stalk may play roles in fruit formation, they do not contribute to the formation of the pericarp in a true fruit.
- The thalamus is involved in some fruits (like apples) but is not a general contributor to pericarp formation.
- The outer integument of the ovule develops into the seed, not the pericarp.
- The stalk may dissolve during fruit formation and does not contribute to the pericarp.

5. **Conclusion**:
- The correct answer to the question is that the structure of the flower which forms the pericarp in a true fruit is the **wall of the ovary**.

### Final Answer:
The structure of the flower which forms the pericarp in a true fruit is the **wall of the ovary**.

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