Select the mismatched pair of organism and its mode of multiplication.

Explanation

To solve the question of selecting the mismatched pair of organism and its mode of multiplication, we will analyze each option provided in the question.

### Step-by-Step Solution

1. **Identify the first pair: Agave and Oxalis through Bulbils**
- **Explanation**: Agave and Oxalis reproduce through bulbils. Bulbils are modified leaves that grow in the axils of the plant. When they fall off, they can grow into new plants.
- **Conclusion**: This pair is correctly matched.

2. **Identify the second pair: Amoeba and Paramecium**
- **Explanation**: Amoeba reproduces through binary fission and can also undergo multiple fission under unfavorable conditions. Paramecium primarily reproduces through binary fission.
- **Conclusion**: This pair is correctly matched.

3. **Identify the third pair: Chlamydomonas and Eulothrix through Sporangiospores**
- **Explanation**: Chlamydomonas reproduces through multiple fission, not through sporangiospores. Eulothrix also reproduces through multiple fission. Sporangiospores are non-motile spores typically associated with fungi, not with these organisms.
- **Conclusion**: This pair is mismatched.

4. **Identify the fourth pair: Adiantum caudatum through advantageous buds present at leaf tips**
- **Explanation**: Adiantum caudatum, a type of fern, reproduces through advantageous buds that grow at the tips of leaves. These buds can fall off and develop into new plants.
- **Conclusion**: This pair is correctly matched.

### Final Answer
The mismatched pair of organism and its mode of multiplication is **Chlamydomonas and Eulothrix through Sporangiospores**.

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