Both, autogamy and geitonogamy are prevented in

Options

A. Papaya
B. Cucumber
C. Castor
D. Maize.

Answer

**Step-by-Step Solution:**

1. **Define Autogamy and Geitonogamy:**
- Autogamy is the process where pollen from a flower is transferred to the stigma of the same flower. This means self-pollination occurs within the same flower.
- Geitonogamy refers to the transfer of pollen from one flower to another flower on the same plant. This is a form of cross-pollination but still occurs within the same individual plant.

2. **Identify the Characteristics of the Plants:**
- **Papaya:** This plant is dioecious, meaning it has separate male and female plants. Therefore, autogamy cannot occur since there are no male and female parts on the same plant, and geitonogamy is also not possible as the pollen cannot be transferred between different plants.
- **Cucumber, Castor, and Maize:** These plants are monoecious, meaning they have both male and female flowers on the same plant. However, they can still prevent autogamy and geitonogamy due to their flower structure and timing of flower maturation.

3. **Conclusion:**
- Since both autogamy and geitonogamy are prevented in papaya due to its dioecious nature, and in cucumber, castor, and maize due to their specific reproductive structures and mechanisms, the answer to the question is that both autogamy and geitonogamy are prevented in these plants.

4. **Final Answer:**
- The correct answer is that both autogamy and geitonogamy are prevented in **Papaya, Cucumber, Castor, and Maize**.

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