Cleistogamous flowers are found in

Options

A. Arachis hypogea
B. Solanum tuberosum
C. Cucumis melo
D. Allium cepa.

Answer

**Step-by-Step Solution:**

1. **Understanding Cleistogamous Flowers**: Cleistogamous flowers are defined as flowers that remain closed throughout their lifetime. This characteristic allows them to self-pollinate, a process known as autogamy.

2. **Identifying the Purpose of Cleistogamous Flowers**: The primary purpose of these flowers is to ensure self-pollination. Since the anthers and stigma are in close proximity, pollen can easily transfer from the anther to the stigma without the need for external pollinators.

3. **Analyzing the Options**:
- **Arachis hypogea**: Commonly known as the peanut, this plant is known to produce cleistogamous flowers.
- **Solanum tuberosum**: This is the potato plant, which typically has chasmogamous flowers that require external pollination.
- **Cucumis melo**: Known as the melon plant, it also has chasmogamous flowers.
- **Allium cepa**: This is the onion plant, which again has chasmogamous flowers.

4. **Conclusion**: Based on the characteristics of cleistogamous flowers and the analysis of the options, the correct answer is **Arachis hypogea**.

**Final Answer**: Cleistogamous flowers are found in **Arachis hypogea**.

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