Abnormal increase in number of WBC is  

Options

A. lecocytosis
B. leucocytopaenia
C. leukemia
D. all the above

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term that describes an abnormal increase in the number of white blood cells (WBC).

2. **Identifying the Options**: The options provided are:
- A) Leucocytosis
- B) Leucocytopenia
- C) Leukemia
- D) All of the above

3. **Analyzing Each Option**:
- **Leucocytosis**: This term refers specifically to an increase in the number of white blood cells, defined as more than 11,000 cells per microliter of blood. It is often a response to infection or other stimuli.
- **Leucocytopenia**: This term indicates a decrease in the number of white blood cells, which is the opposite of what the question is asking.
- **Leukemia**: This is a type of cancer that affects blood-forming tissues, leading to the production of abnormal white blood cells. While it involves an increase in WBCs, it is a specific disease rather than a general term for increased WBC count.
- **All of the above**: This option suggests that all terms are correct, which is not the case since leucocytopenia is not related to an increase in WBC.

4. **Conclusion**: The correct answer is **A) Leucocytosis**, as it directly refers to the abnormal increase in the number of white blood cells.

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