Which of the following multiply by the process of fragmentation?

Options

A. Planaria
B. Filamentous algae
C. Fungi
D. All of these

Answer

To determine which organisms multiply by the process of fragmentation, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understanding Fragmentation**: Fragmentation is a type of asexual reproduction where an organism breaks into fragments, and each fragment can grow into a new individual. This process is common in certain organisms, particularly in lower life forms.

2. **Analyzing Planaria**:
- Planaria are flatworms that belong to the phylum Platyhelminthes.
- They can reproduce asexually through fragmentation. If a Planaria is cut into pieces (for example, due to water currents), each piece can regenerate into a complete organism.
- **Conclusion**: Planaria can multiply by fragmentation.

3. **Analyzing Filamentous Algae**:
- Filamentous algae, such as Cladophora and Spirogyra, can also reproduce through fragmentation.
- When physical factors (like water currents) affect them, they can break into fragments, and each fragment can grow into a new filamentous algae.
- **Conclusion**: Filamentous algae can multiply by fragmentation.

4. **Analyzing Fungi**:
- Fungi typically reproduce through spores, but they can also reproduce vegetatively.
- In vegetative reproduction, certain parts of the fungus (like hyphae) can break off and grow into new fungi. However, this is not the same as fragmentation in the strict sense.
- **Conclusion**: While fungi can reproduce vegetatively, they do not primarily multiply by fragmentation.

5. **Final Evaluation**:
- Based on the analysis, both Planaria and filamentous algae reproduce by fragmentation.
- Fungi do not primarily reproduce by fragmentation, but rather through spores and vegetative methods.

### Answer:
The organisms that multiply by the process of fragmentation are **Planaria** and **filamentous algae**.

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