Which one of the following is a pair of endangered species?
(a) Hornbill and Indian Aconite
(b) Indian peacock and Carrot Grass
(c) Garden Lizard and Mexican Poppy
(d) Rhesus Monkey and Sal Tree.

Options

A. Hornbill and Indian Aconite
B. Indian peacock and Carrot Grass
C. Garder Lizard and Mexican Poppy
D. Phesus Monkey and Sal Tree.

Answer

To determine which pair of species is endangered, we need to analyze each option based on the criteria of endangered species as defined by the IUCN Red List. Endangered species are those that are at risk of extinction due to various factors, including habitat loss, hunting, and environmental changes.

**Step-by-Step Solution:**

1. **Understand the Definition of Endangered Species:**
- According to the IUCN Red List, endangered species are those whose populations are declining at a significant rate and are likely to become extinct if the factors causing the decline are not addressed.

2. **Examine Each Option:**
- **Option (a): Hornbill and Indian Aconite**
- Hornbills are birds that are often threatened due to habitat loss. Indian Aconite (Aconitum heterophyllum) is a plant that is also considered endangered due to overharvesting and habitat destruction.
- **Conclusion:** Both species are considered endangered.

- **Option (b): Indian Peacock and Carrot Grass**
- The Indian Peacock (Pavo cristatus) is not endangered; it is widespread and has a stable population. Carrot Grass (Parthenium hysterophorus) is an invasive species and not endangered.
- **Conclusion:** This pair is not endangered.

- **Option (c): Garden Lizard and Mexican Poppy**
- The Garden Lizard (Calotes versicolor) is common and not endangered. Mexican Poppy (Eschscholzia californica) is also not listed as endangered.
- **Conclusion:** This pair is not endangered.

- **Option (d): Rhesus Monkey and Sal Tree**
- The Rhesus Monkey (Macaca mulatta) is not endangered and is found in many areas. The Sal Tree (Shorea robusta) is also not endangered and is common in its native habitat.
- **Conclusion:** This pair is not endangered.

3. **Identify the Correct Answer:**
- Based on the analysis, the only pair that consists of endangered species is **Option (a): Hornbill and Indian Aconite**.

**Final Answer: (a) Hornbill and Indian Aconite**

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