Pili are appendages of
(a) Mycoplasma
(b) Bacteria
(c) Viruses
(d) Algae

Options

A. Mycoplasma
B. Bacteria
C. Viruses
D. Algae.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the organism that possesses pili, which are hair-like appendages.

2. **Analyzing the Options**:
- **Option A: Mycoplasma**: Mycoplasma are a type of bacteria that lack a cell wall and do not have pili.
- **Option B: Bacteria**: Many bacteria have pili, which are hair-like structures that protrude from their surface.
- **Option C: Viruses**: Viruses do not have cellular structures like pili; they are much simpler and do not possess appendages.
- **Option D: Algae**: Algae are eukaryotic organisms and do not have pili.

3. **Identifying the Correct Answer**: Since pili are specifically associated with bacteria and not with the other options, the correct answer is **Option B: Bacteria**.

4. **Conclusion**: Pili are appendages found in bacteria, which assist in various functions such as locomotion and attachment.

**Final Answer**: (b) Bacteria

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