Nucleated RBCs are found in

Options

A. Man
B. Rat
C. Rabbit
D. Frog

Answer

To answer the question "Nucleated RBCs are found in?", we need to analyze the options provided and understand where nucleated red blood cells (RBCs) can be found.

### Step-by-Step Solution:

1. **Understanding Nucleated RBCs**:
- Nucleated red blood cells are immature red blood cells that still contain a nucleus. In mammals, mature red blood cells typically lose their nucleus to maximize space for hemoglobin, which is crucial for oxygen transport.

2. **Analyzing the Options**:
- **Option 1: Man**:
- In humans, mature red blood cells are enucleated (they do not have a nucleus). Therefore, this option is incorrect.

- **Option 2: Rat**:
- Similarly, in rats, the red blood cells are also enucleated. Thus, this option is also incorrect.

- **Option 3: Rabbit**:
- Like humans and rats, rabbits also have enucleated red blood cells. Therefore, this option is incorrect as well.

- **Option 4: Frog**:
- Frogs are amphibians, and their red blood cells are nucleated. The nucleus is present in the center of the red blood cells. Hence, this option is correct.

3. **Conclusion**:
- Based on the analysis, the correct answer is that nucleated RBCs are found in **Frogs** (Option 4).

### Final Answer:
Nucleated RBCs are found in **Frogs**.