Calcium deposition and larvicidal properties are found in

Options

A. Diatoms
B. Oscillatoria
C. Chara
D. Caulerpa.

Answer

To solve the question regarding which organism possesses calcium deposition and larvicidal properties, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Organisms**: The question provides four options: Diatoms, Oscillatoria, Cara, and Kauliripa. We need to analyze each option to determine if they have calcium deposition and larvicidal properties.

2. **Analyze Diatoms**:
- Diatoms are microscopic sea organisms known for their role in aquatic food chains.
- They do not exhibit calcium deposition or larvicidal properties.
- **Conclusion**: Diatoms are not the correct answer.

3. **Analyze Oscillatoria**:
- Oscillatoria is a type of blue-green algae (cyanobacteria).
- It is primarily researched for its potential in producing BHT (butylated hydroxytoluene), an antioxidant.
- It does not have calcium deposition or larvicidal properties.
- **Conclusion**: Oscillatoria is not the correct answer.

4. **Analyze Cara**:
- Cara is a member of the class Charophyceae, which includes green algae.
- It is known to have larvicidal properties, specifically used to control mosquito larvae.
- Additionally, it serves as a cheap source of calcium, especially in acidic conditions.
- **Conclusion**: Cara possesses both calcium deposition and larvicidal properties, making it a strong candidate.

5. **Analyze Kauliripa**:
- Kauliripa is known for its antibacterial and antifungal properties.
- However, it does not have larvicidal properties.
- **Conclusion**: Kauliripa is not the correct answer.

6. **Final Conclusion**: Based on the analysis, the organism that possesses both calcium deposition and larvicidal properties is **Cara**.

### Final Answer:
Calcium deposition and larvicidal properties are found in **Cara**.

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