Undifferentiated cell during RBC formation is :

Options

A. Myeloblast
B. Erythroblast
C. Normoblast
D. Lymphoid cells

Answer

To answer the question, "Undifferentiated cell during RBC formation is:", we will analyze the options provided and determine which one correctly identifies the undifferentiated cell involved in the formation of red blood cells (RBCs).

### Step-by-Step Solution:

1. **Understanding the Question**:
- The question asks for the type of undifferentiated cell that is involved in the formation of red blood cells (RBCs).

2. **Analyzing the Options**:
- **Myeloblast**:
- Myeloblasts are immature white blood cells (WBCs). Since the question is specifically about red blood cells, this option is incorrect.
- **Erythroblast**:
- Erythroblasts are indeed immature red blood cells. They are the precursor cells that develop into mature RBCs. This option is a strong candidate for the correct answer.
- **Normoblast**:
- Normoblasts are also immature RBCs; however, they are further along in the development process and contain hemoglobin. They are not considered undifferentiated cells. Thus, this option is incorrect.
- **Lymphoid Cells**:
- Lymphoid cells are a type of white blood cell involved in the immune response. They do not play a role in the formation of red blood cells, making this option incorrect as well.

3. **Conclusion**:
- After analyzing all the options, the correct answer to the question is **Erythroblast**, as they are the undifferentiated cells that develop into red blood cells.

### Final Answer:
The undifferentiated cell during RBC formation is **Erythroblast**.