White blood cells help in (A) clotting of blood (B) transport of O2 (C) transport of CO2 (D) destroying harmful germs

Options

A. clotting of blood
B. transport of `O_2`
C. transport of `CO_2`
D. destroying harmful germs

Answer

To solve the question regarding the function of white blood cells, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Function of White Blood Cells (WBCs)**:
- White blood cells are crucial components of the immune system. Their primary role is to protect the body against infections and foreign invaders.

2. **Identify the Types of White Blood Cells**:
- WBCs can be classified into several types, including granulocytes (which include eosinophils, neutrophils, and basophils) and lymphocytes (which include T-cells and B-cells). Each type has specific functions related to immune response.

3. **Analyze the Given Options**:
- (A) Clotting of blood: This is primarily the function of platelets, not white blood cells.
- (B) Transport of O2: This is the function of red blood cells (RBCs).
- (C) Transport of CO2: This is also primarily the function of red blood cells.
- (D) Destroying harmful germs: This is a key function of white blood cells, as they actively seek out and eliminate pathogens.

4. **Select the Correct Answer**:
- Based on the analysis, the correct answer is (D) destroying harmful germs, as this aligns with the primary role of white blood cells in the immune response.

### Final Answer:
(D) destroying harmful germs

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