Oval and nucleated RBC is found in

Options

A. man
B. rat
C. rabbit
D. frog

Answer

To solve the question "Oval and nucleated RBC is found in," we will follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question is asking about the type of organism that has oval and nucleated red blood cells (RBCs).

2. **Define RBCs**: Red blood cells (RBCs), also known as erythrocytes, are crucial components of blood responsible for transporting oxygen throughout the body.

3. **Characteristics of Mammalian RBCs**: In mammals, RBCs are typically biconcave in shape and lack a nucleus (enucleated) when mature. This is a significant characteristic of mammalian RBCs.

4. **Identify the Organisms in the Options**:
- **Man**: A mammal, which has enucleated RBCs.
- **Rat**: Another mammal, which also has enucleated RBCs.
- **Rabbit**: Yet another mammal, with enucleated RBCs.
- **Frog**: An amphibian, which has oval and nucleated RBCs.

5. **Analyze the Options**: Since the question specifically asks for oval and nucleated RBCs, we can eliminate the options that are mammals (man, rat, rabbit) because they do not fit the description.

6. **Select the Correct Answer**: The only organism among the options that has oval and nucleated RBCs is the frog, which is an amphibian.

7. **Conclusion**: Therefore, the correct answer is **Frog**.

### Final Answer:
The correct answer is **Frog**.

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