What names is given to those species :
a) That are on the verge of vanishing from earth ?

Options

A. Extinct species
B. Endangered species
C. Tropical species
D. None of the above

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name given to species that are on the verge of vanishing from Earth. This indicates that these species are at risk of extinction.

2. **Identifying Key Terms**: The term "on the verge of vanishing" suggests that the species in question are not yet extinct but are facing a high risk of extinction if conservation efforts are not made.

3. **Defining the Terms**:
- **Extinct Species**: These are species that no longer exist anywhere on Earth.
- **Endangered Species**: These are species that are at a high risk of extinction in the near future.
- **Tropical Species**: These are species that are found in tropical regions, but this term does not relate to the risk of extinction.
- **None of the Above**: This option would imply that none of the previous terms apply, which is not the case here.

4. **Choosing the Correct Answer**: Based on the definitions, the correct term for species that are on the verge of vanishing from Earth is "endangered species."

5. **Examples of Endangered Species**: Some examples of endangered species include the Asiatic lion, tiger, and cheetah. These species are currently facing threats that could lead to their extinction if not addressed.

6. **Conclusion**: Therefore, the name given to species that are on the verge of vanishing from Earth is "endangered species."

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