Which of the following is correctly matched?

Options

A. Aerenchyma -Opuntia
B. Age pyramid -Biome
C. Partheniu mhysterophorus -Threat to biodiversity
D. Stratification -Population

Explanation

To solve the question "Which of the following is correctly matched?", we need to analyze each option provided in the question.

### Step-by-Step Solution:

1. **Analyze the First Option: Aaron, Kyma, and Apunji**
- **Explanation**: Aaron, Kyma, and Apunji refer to air sacs found in aquatic plants that help them float. However, this option does not represent a correct match as it does not align with a specific biological term or concept.
- **Conclusion**: This is not a correct match.

2. **Analyze the Second Option: Age Pyramid and Biome**
- **Explanation**: An age pyramid represents the distribution of various age groups in a population, typically of humans or other species. A biome, on the other hand, is a large ecological area on the earth's surface, with flora and fauna adapting to their environment. Therefore, an age pyramid cannot be correctly matched with a biome.
- **Conclusion**: This is not a correct match.

3. **Analyze the Third Option: Parthenium and Threat to Biodiversity**
- **Explanation**: Parthenium, also known as carrot grass, is indeed a significant threat to biodiversity. It is an alien species that was introduced to India through imported wheat and has since proliferated, negatively impacting local ecosystems. This option correctly matches Parthenium with its role as a threat to biodiversity.
- **Conclusion**: This is a correct match.

4. **Analyze the Fourth Option: Stratification**
- **Explanation**: Stratification refers to the layering of different species or groups within an ecosystem, such as trees, shrubs, and grasses. It is not specifically related to population dynamics but rather to larger ecological structures. Thus, this does not represent a correct match.
- **Conclusion**: This is not a correct match.

### Final Answer:
The correctly matched option is **Parthenium and Threat to Biodiversity**.

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