Binary fission is a regular mode of multiplication in

Options

A. Yeast
B. Bacteria
C. Marchantia
D. Mosses.

Answer

**Step-by-Step Solution:**

1. **Understanding Binary Fission**: Binary fission is a type of asexual reproduction where an organism divides into two equal parts. This process is common in unicellular organisms.

2. **Identifying the Organisms**: The question provides four options: A. Yeast, B. Bacteria, C. Marchantia, and D. Mosses. We need to determine which of these organisms commonly reproduce through binary fission.

3. **Analyzing Each Option**:
- **A. Yeast**: Yeast typically reproduces by budding, not binary fission.
- **B. Bacteria**: Bacteria reproduce by binary fission, where the cell divides into two identical daughter cells after duplicating its genetic material.
- **C. Marchantia**: Marchantia is a type of liverwort that reproduces sexually and asexually through structures called gemmae, not binary fission.
- **D. Mosses**: Mosses also reproduce sexually and asexually, but not through binary fission.

4. **Conclusion**: Since binary fission is a regular mode of multiplication in bacteria, the correct answer is option B.

**Final Answer**: B. Bacteria

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