Which of the following is correctly matched ?

Options

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

Answer

To determine which of the following options is correctly matched, we will analyze each option one by one.

### Step-by-Step Solution:

1. **Analyzing Option 1: Pythenium hystrophorus and its relation to biodiversity**
- Pythenium hystrophorus is known to be a toxic plant that affects farm animals and can cause allergic reactions in humans.
- It is considered an invasive species, which can significantly impact biodiversity.
- Therefore, this option is correctly matched with "3-8 for biodiversity."

2. **Analyzing Option 2: Stratification and Population**
- Stratification refers to the layering or arrangement of different levels within an ecosystem, typically concerning vegetation or habitats.
- It is not directly related to population dynamics but rather to ecological structure.
- Hence, this option is incorrectly matched.

3. **Analyzing Option 3: Erenkaima and Aponchia**
- Erenkaima is a type of tissue found in hydrophytes (aquatic plants).
- Aponchia, on the other hand, is typically found in desert environments.
- Since these two are from different ecological contexts, this option is also incorrectly matched.

4. **Analyzing Option 4: Age Pyramid and Bio**
- An age pyramid is a graphical representation of the distribution of various age groups in a population.
- It is not specifically matched with "bio" but rather illustrates population distribution.
- Therefore, this option is incorrectly matched as well.

### Conclusion:
After analyzing all options, we conclude that **Option 1: Pythenium hystrophorus and its relation to biodiversity is the only correctly matched pair.**

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