The viability of pollen grains is highly variable . The least pollen variable . The least pollen viability will be observed in :

Options

A. Soybeans
B. Potato
C. Peach
D. Rice

Answer

To solve the question regarding the viability of pollen grains and determine which plant has the least pollen viability, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Pollen Viability**:
- Pollen viability refers to the ability of pollen grains to germinate and successfully fertilize the ovule. It can vary significantly among different plant species.

2. **Identifying the Options**:
- The question provides several options, including soybean, potato, and rice. We need to analyze the viability of pollen grains in these plants.

3. **Analyzing the Options**:
- **Soybean**: This is a dicotyledonous plant. Dicotyledons generally have a moderate to high pollen viability.
- **Potato**: Also a dicotyledon, potatoes typically exhibit good pollen viability as well.
- **Rice**: This is a monocotyledonous plant. Monocots often have lower pollen viability compared to dicots.

4. **Comparing Pollen Viability**:
- Among the options, soybean and potato (both dicots) are known to have relatively high pollen viability. In contrast, rice, being a monocot, tends to have lower pollen viability.

5. **Conclusion**:
- Based on the analysis, the plant with the least pollen viability among the given options is **rice**.

### Final Answer:
The least pollen viability will be observed in **rice**.

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