Archaebacteria shows similarity with Mycoplasma in having :

Options

A. pigmented membrane
B. DNA associated with histone protein
C. rigid cell wall
D. `70S` ribosomes

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the similarity between Archaebacteria and Mycoplasma, specifically focusing on what they have in common.

2. **Analyzing the Options**:
- **Option 1: Pigmented Membrane**: This option is incorrect. Neither Archaebacteria nor Mycoplasma is characterized by pigmented membranes.
- **Option 2: DNA associated with histone protein**: This option is also incorrect. While Archaebacteria do have DNA associated with histone proteins, Mycoplasma does not have histones associated with its DNA.
- **Option 3: Rigid cell wall**: This option is incorrect. Mycoplasma is known for lacking a rigid cell wall, while Archaebacteria have different types of cell walls that are not rigid in the same way as those in Eubacteria.
- **Option 4: 70S ribosomes**: This option is correct. Both Archaebacteria and Mycoplasma possess 70S ribosomes, which is a significant similarity between the two.

3. **Conclusion**: The correct answer is that Archaebacteria shows similarity with Mycoplasma in having 70S ribosomes.

**Final Answer**: Archaebacteria shows similarity with Mycoplasma in having 70S ribosomes.

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