According to IUCN Red list , during the last two decades the maximum increase in the number of the threatened species is among :

Options

A. Mammals
B. Amphibians
C. Reptiles
D. Birds.

Answer

**Step-by-Step Solution:**

1. **Understand the IUCN Red List**: The International Union for Conservation of Nature (IUCN) maintains the Red List, which categorizes species based on their conservation status. It includes species that are threatened with extinction.

2. **Identify Threatened Species**: Threatened species are classified into different categories, including vulnerable, endangered, and critically endangered. These categories indicate the level of threat each species faces.

3. **Examine Trends Over Two Decades**: The question specifically asks about trends over the last two decades. This requires looking at data on species that have been added to the threatened categories during this time frame.

4. **Focus on Specific Groups**: The question asks for the group with the maximum increase in threatened species. It is important to consider various groups of organisms, such as mammals, birds, reptiles, amphibians, and plants.

5. **Analyze Data**: According to the IUCN Red List updates, amphibians have shown a significant increase in the number of threatened species over the last two decades. This is attributed to factors such as habitat loss, climate change, pollution, and disease.

6. **Conclude the Answer**: Based on the analysis, the group with the maximum increase in the number of threatened species in the last two decades is amphibians.

**Final Answer**: The maximum increase in the number of threatened species according to the IUCN Red List during the last two decades is among amphibians.

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