The phenomenon of apical dominance is strengthened by

Options

A. Removal of the tip
B. Removal of leaves
C. Auxin production
D. Production of fruits

Answer

### Step-by-Step Solution:

1. **Understanding Apical Dominance**:
- Apical dominance is a phenomenon where the main, central stem of the plant grows more strongly than the other side stems (lateral buds). This is primarily due to the presence of the apical bud, which produces hormones that inhibit the growth of lateral buds.

2. **Role of Auxins**:
- The primary hormone involved in apical dominance is auxin. It is produced at the apical bud and promotes growth in that region while inhibiting the growth of lateral buds. This means that the higher concentration of auxins at the top suppresses the growth of buds lower down.

3. **Factors Affecting Apical Dominance**:
- The phenomenon can be influenced by various factors, including the removal of certain parts of the plant. The question presents options related to the removal of leaves, teeth, and the production of oxygen and fruit.

4. **Analyzing the Options**:
- **Removal of Teeth**: This option is irrelevant to plant biology.
- **Removal of Leaves**: While removing leaves can affect the overall growth, it does not specifically strengthen apical dominance.
- **Oxygen Production**: Oxygen is a byproduct of photosynthesis and does not directly influence apical dominance.
- **Production of Fruit**: This is a result of successful flowering and fertilization, not a factor that strengthens apical dominance.

5. **Conclusion**:
- The removal of the apical bud (decapitation) leads to the release of the lateral buds from the inhibitory effects of auxins, allowing them to grow. Therefore, the phenomenon of apical dominance is strengthened by the presence of the apical bud, not by the removal of any part.

### Final Answer:
The phenomenon of apical dominance is strengthened by the presence of the apical bud, which produces auxins that inhibit the growth of lateral buds.

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