A large number of unknown species of plants and animals are believed to be present in :-

Options

A. Temperate forests
B. Antarctica
C. Taiga
D. Tropical forest

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where a large number of unknown species of plants and animals are believed to be present. This requires us to analyze different types of forests and their biodiversity.

2. **Evaluating Forest Types**:
- **Temperate Forest**: These forests experience distinct seasons, including cold winters. The biodiversity is moderate due to the seasonal changes and adaptations required by organisms to survive the cold.
- **Taiga**: This biome is characterized by long, cold winters and short summers. The harsh conditions limit the variety of species that can thrive here, leading to lower biodiversity.
- **Antarctica**: This region has an extremely cold climate with permanent ice cover and very little sunlight. The conditions are not conducive to supporting a diverse range of life forms.
- **Tropical Forest**: These forests are known for their warm climate and high levels of rainfall. They receive abundant sunlight, which is crucial for photosynthesis and supports a vast array of plant and animal life.

3. **Analyzing Biodiversity**: Among the four options, tropical forests are recognized for having the highest biodiversity due to their favorable climate, abundant sunlight, and consistent rainfall. This environment allows for a greater number of species, including many that are still unknown to science.

4. **Conclusion**: Based on the analysis, the tropical forest is the most likely habitat for a large number of unknown species of plants and animals.

5. **Final Answer**: The answer is **Tropical Forest**.

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