The animals which possess backbone are called P, e.g., Q and R. Here P, Q, and R are respectively

Options

A. vertebrates, birds, reptiles
B. vertebrates, insects, snails
C. invertebrates, snakes, birds
D. invertebrates, humans, reptiles.

Explanation

**Step-by-Step Solution:**

1. **Identify the Group of Animals with Backbone:**
- The animals that possess a backbone are called **vertebrates**. This classification is based on the presence of a spinal column or backbone.

2. **Define the Term P:**
- In this context, P refers to the group of animals known as **vertebrates**.

3. **Provide Examples of Vertebrates:**
- Examples of vertebrates include:
- **Q:** Birds (e.g., sparrows, eagles)
- **R:** Reptiles (e.g., snakes, lizards)

4. **Summarize the Information:**
- Therefore, we can summarize that:
- P = Vertebrates
- Q = Birds
- R = Reptiles

**Final Answer:**
P = Vertebrates, Q = Birds, R = Reptiles.

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