Tailed bacteriophages are

Options

A. Non-motile
B. Actively motile in water
C. Motile on bacterial surface
D. Motile on surface of plant leaves.

Answer

**Step-by-Step Solution:**

1. **Understanding Tailed Bacteriophages**: Tailed bacteriophages are a type of virus that infects bacteria. They have a unique structure that includes a head and a tail, which is used to inject their genetic material into the host bacterial cell.

2. **Analyzing the Options**: The question provides four options regarding the motility of tailed bacteriophages:
- Non-motile
- Actively motile in water
- Motile on bacterial surface
- Motile on the surface of plant leaf

3. **Identifying Characteristics**: Tailed bacteriophages do not have the ability to move independently. They rely on the movement of the liquid medium (like water) or the surfaces they are on to reach their bacterial hosts.

4. **Conclusion**: Based on the characteristics of tailed bacteriophages, they are classified as non-motile because they do not exhibit active movement. Instead, they attach to bacteria and inject their genetic material.

5. **Final Answer**: Therefore, the correct answer is that tailed bacteriophages are **non-motile**.

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