In which one of the following pollination is autogamous ?

Options

A. Cleistogamy
B. Geitonogamy
C. Xenogamy
D. Chasmogamy

Answer

To determine which type of pollination is autogamous, we need to understand the definitions and characteristics of the given options: clistogamy, genetogamy, genogamy, and chasmogamy.

### Step-by-Step Solution:

1. **Understanding Autogamy**:
- Autogamy refers to self-pollination, where pollen from the anther of a flower fertilizes the stigma of the same flower. This means that the pollination occurs within the same flower.

2. **Analyzing Clistogamy**:
- Clistogamous flowers are those that do not open at all. In these flowers, the anthers and stigma are in close proximity, allowing for self-pollination to occur easily. Since the pollen is transferred within the same flower, clistogamy is a form of autogamy.

3. **Examining Genetogamy**:
- Genetogamy involves the transfer of pollen from the anther of one flower to the stigma of another flower on the same plant. This is not self-pollination, as it involves different flowers, hence it is not autogamous.

4. **Considering Genogamy**:
- Genogamy refers to the transfer of pollen between different plants. Since this involves different plants and different flowers, it does not qualify as autogamy.

5. **Looking into Chasmogamy**:
- Chasmogamous flowers are characterized by open petals, which are conducive to cross-pollination. The exposure of the petals increases the chances of pollen transfer between different flowers, making it a form of cross-pollination rather than autogamy.

6. **Conclusion**:
- Based on the definitions and characteristics analyzed, the correct answer is **Clistogamy**, as it represents a type of pollination where self-pollination occurs within the same flower.

### Final Answer:
**Clistogamy** is the type of pollination that is autogamous.

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