A bird introduced from another country became a serious pest due to -

Options

A. Better adaptation to new area
B. More sexual reproduction
C. Better nesting habitats
D. Absence of natural competition

Answer

To answer the question about why a bird introduced from another country became a serious pest, we can analyze the options provided.

### Step-by-Step Solution:

1. **Understanding the Context**:
- The question refers to an introduced bird species that has become a pest in a new environment. This often occurs when a species is brought into a new habitat where it lacks natural predators or competitors.

2. **Analyzing the Options**:
- **Option 1: Better adaptation to new area**: While adaptation can play a role, it is not the primary reason for becoming a pest.
- **Option 2: More sexual reproduction**: Increased reproduction can lead to population growth, but it is not the sole factor for becoming a pest.
- **Option 3: Better nesting habitats**: This could help in the survival of the species but does not directly explain pest behavior.
- **Option 4: Absence of natural competition**: This is a key factor. Without natural competitors or predators, the introduced species can thrive and reproduce unchecked, leading to pest status.

3. **Conclusion**:
- The best answer is **Option 4: Absence of natural competition**. When a species is introduced to a new environment without its natural enemies, it can proliferate rapidly and become a pest.

### Final Answer:
A bird introduced from another country became a serious pest due to the **absence of natural competition**.

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