Which of the following is pathogenic an plants and animals and lack a cell wall

Options

A. Archaebacteria
B. Eubacteria
C. Cyanobacteria
D. Mycoplasma

Explanation

To solve the question "Which of the following is pathogenic in plants and animals and lacks a cell wall?", we will analyze the characteristics of the options provided, focusing on their pathogenicity and cell wall presence.

### Step-by-Step Solution:

1. **Understanding Pathogenicity**:
- Pathogenic organisms are those that can cause disease in their hosts. In this case, we are looking for organisms that can affect both plants and animals.

2. **Identifying the Options**:
- The options likely include different types of bacteria or microorganisms. We need to evaluate each option based on their characteristics.

3. **Analyzing Bacteria**:
- Most bacteria have a cell wall made of peptidoglycan. This is a key feature that distinguishes them from other microorganisms.

4. **Identifying Mycoplasma**:
- Mycoplasma is a unique group of bacteria that lack a cell wall. They are known to be pathogenic to both plants and animals, making them a potential answer to the question.

5. **Evaluating Other Options**:
- Other types of bacteria, such as eubacteria and archaebacteria, typically have a cell wall and are not known to be pathogenic to both plants and animals.
- Eubacteria includes cyanobacteria, which also have a cell wall.

6. **Conclusion**:
- Based on the analysis, Mycoplasma is the only organism that is pathogenic to both plants and animals and lacks a cell wall.

### Final Answer:
The correct answer is **Mycoplasma**.

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