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

Options

A. Temperature 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 implies we need to identify a region known for high biodiversity.

2. **Analyzing the Options**: The options provided are:
- Temperate forest
- Antarctica
- Taiga
- Tropical forest

3. **Evaluating Each Option**:
- **Temperate Forest**: These forests have moderate climates and seasonal changes, but they do not have the highest biodiversity compared to tropical forests.
- **Antarctica**: This region is extremely cold, covered in ice, and has very few species of plants and animals due to harsh conditions. It is not known for biodiversity.
- **Taiga**: Also known as boreal forests, these regions experience cold winters and have fewer species compared to tropical forests.
- **Tropical Forest**: These forests receive maximum sunlight and have a warm climate year-round, which supports a vast array of plant and animal life. They are known for having the highest biodiversity.

4. **Conclusion**: Based on the analysis, the tropical forest is the region believed to have a large number of unknown species of plants and animals due to its optimal conditions for life.

5. **Final Answer**: The correct option is **tropical forest**.

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