The average lifespan is the highest for :

Options

A. RBC
B. Neutrophils
C. Eosinophils
D. Basophils

Answer

To determine which of the given options has the highest average lifespan, we need to analyze the lifespan of each type of blood cell mentioned in the question.

### Step-by-Step Solution:

1. **Identify the Types of Blood Cells**:
- The question refers to Red Blood Cells (RBC) and White Blood Cells (WBC). WBC can be further categorized into different types, such as neutrophils, eosinophils, and basophils.

2. **Determine the Lifespan of Red Blood Cells (RBC)**:
- The average lifespan of RBCs is approximately **120 days**.

3. **Determine the Lifespan of White Blood Cells (WBC)**:
- The lifespan of WBCs varies based on their type:
- Neutrophils: **2 to 5 days**
- Eosinophils: **7 to 12 days**
- Basophils: **12 to 15 days**
- The average lifespan of WBCs can be considered around **12 to 20 days**, depending on the specific type of WBC.

4. **Comparison of Lifespans**:
- RBCs: **120 days**
- WBCs: **12 to 20 days** (maximum lifespan among WBCs is still much lower than that of RBCs).

5. **Conclusion**:
- Since the lifespan of RBCs (120 days) is significantly longer than that of any type of WBC (maximum of 20 days), we conclude that the average lifespan is the highest for **Red Blood Cells (RBC)**.

### Final Answer:
The average lifespan is the highest for **Red Blood Cells (RBC)**.

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