Which part of the world has high density of organisms ?

Options

A. Deciduous forests
B. Grasslands
C. Savannas
D. Tropical rain forests

Explanation

**Step-by-Step Solution:**

1. **Understanding Biodiversity**: Begin by defining biodiversity, which refers to the variety of living organisms on Earth, including plants, animals, and microorganisms. It is measured by the number of species in a given area.

2. **Identifying Regions of High Biodiversity**: Recognize that different regions of the world have varying levels of biodiversity. The question asks for the area with the highest density of organisms.

3. **Evaluating Options**: Consider the options provided. The tropical rainforest is known for having the highest biodiversity due to its unique environmental conditions.

4. **Reasons for High Biodiversity in Tropical Rainforests**:
- **Solar Energy**: Tropical rainforests receive a high amount of solar energy, which supports a greater primary productivity.
- **Location**: These forests are located near the equator, where climatic conditions are optimal for a wide variety of species.
- **Time for Speciation**: Tropical rainforests have existed for a long time without significant environmental disturbances, allowing for the development of numerous species through speciation.

5. **Conclusion**: Based on the factors mentioned, the tropical rainforest is identified as the part of the world with the highest density of organisms.

6. **Final Answer**: The correct answer is the **tropical rainforest**.

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