Find out the incorrect statement in the following regarding the monera`:-`

Options

A. Heterotrophic bacteria are most abundant in nature.
B. Bacterial structure is very complex and they have very simple behaviour.
C. Bacterial reproduce mainly by fission
D. Archacbacteria differ from other bacteria in having different cell wall structure.

Explanation

To solve the question of identifying the incorrect statement regarding Monera, we will analyze each statement provided.

### Step-by-Step Solution:

1. **Understanding Monera**: Monera is a kingdom that includes all prokaryotic organisms, primarily bacteria. They are characterized by their simple cellular structure without a nucleus.

2. **Analyzing Statement 1**: "Heterotrophic bacteria are the most abundant in nature."
- **Evaluation**: This statement is true. Heterotrophic bacteria, which obtain their food from organic matter, are indeed very abundant in various ecosystems.

3. **Analyzing Statement 2**: "Bacteria structure is very complex and they have simple behavior."
- **Evaluation**: This statement is incorrect. Bacteria have a simple structure (prokaryotic cells) and exhibit complex behaviors, such as forming biofilms, communication through quorum sensing, and various metabolic pathways.

4. **Analyzing Statement 3**: "Bacteria reproduce mainly by fission."
- **Evaluation**: This statement is true. Bacteria primarily reproduce asexually through binary fission, where one cell divides into two identical cells.

5. **Analyzing Statement 4**: "Archaebacteria differ from other bacteria in different cell wall structure."
- **Evaluation**: This statement is true. Archaebacteria have unique cell wall structures that differ from those of eubacteria, contributing to their ability to survive in extreme environments.

6. **Conclusion**: After evaluating all statements, the incorrect statement is the second one: "Bacteria structure is very complex and they have simple behavior."

### Final Answer:
The incorrect statement regarding Monera is: "Bacteria structure is very complex and they have simple behavior."

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