In leukaemia, there is tremendous increase in the numbers of

Options

A. R.B.C.'s
B. Immature cells
C. W.B.C.'s
D. W.B.Cs and immature Leucocytes

Answer

### Step-by-Step Solution:

1. **Understanding Leukemia**:
- Leukemia is a type of cancer that primarily affects the blood and bone marrow. It is characterized by the uncontrolled proliferation of blood cells.

2. **Identifying the Affected Cells**:
- In leukemia, there is a significant increase in the number of white blood cells (WBCs). These cells are crucial for the immune system and help the body fight infections.

3. **Differentiating Between Cell Types**:
- It is important to differentiate between the types of blood cells:
- **RBCs (Red Blood Cells)**: These cells are responsible for carrying oxygen throughout the body. Leukemia does not involve an increase in RBCs.
- **WBCs (White Blood Cells)**: These are the cells that are primarily affected in leukemia. They can be immature or mature forms.
- **Immature Cells**: This term can refer to the early forms of WBCs, which can also proliferate uncontrollably in leukemia.

4. **Conclusion**:
- The correct answer to the question is that in leukemia, there is a tremendous increase in the number of **WBCs (white blood cells)** and **immature leukocytes**.

### Final Answer:
In leukemia, there is a tremendous increase in the numbers of **white blood cells (WBCs)** and **immature leukocytes**.

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