All of the following statement are correct about WBCs except -

Options

A. They are nucleate and least constancy in shape
B. They are lesser in number (6000-8000 per `mm^(3)` blood)
C. They are generally short lived
D. They help in blood clotting

Answer

To solve the question regarding the statements about White Blood Cells (WBCs), let's analyze each statement step by step.

### Step 1: Analyze the First Statement
- **Statement**: WBCs are nucleate and least consistent in shape.
- **Explanation**: This statement is correct. WBCs are indeed nucleated cells, unlike Red Blood Cells (RBCs) which are enucleated. Additionally, WBCs come in various shapes depending on their type (e.g., lymphocytes, neutrophils, etc.).

### Step 2: Analyze the Second Statement
- **Statement**: They are lesser in number, about 6,000 to 8,000 per millimeter cube of blood.
- **Explanation**: This statement is also correct. The normal range for WBCs in the blood is approximately 6,000 to 8,000 cells per cubic millimeter, which is significantly lower than the number of RBCs.

### Step 3: Analyze the Third Statement
- **Statement**: They are generally short-lived.
- **Explanation**: This statement is correct as well. WBCs have a relatively short lifespan, ranging from a few days to several weeks, depending on the type of WBC.

### Step 4: Analyze the Fourth Statement
- **Statement**: They help in blood clotting.
- **Explanation**: This statement is incorrect. WBCs are primarily involved in the immune response and defense against pathogens. Blood clotting is primarily the function of platelets, not WBCs.

### Conclusion
Based on the analysis, the statement that is incorrect about WBCs is the fourth one: "They help in blood clotting." Therefore, the correct answer to the question is option 4.

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