T-cell have a life of

Options

A. 4-5 days
B. 4-5 weeks
C. 4-5 months
D. 4-5 years

Answer

To answer the question regarding the lifespan of T-cells, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Type of Cell**: Understand that T-cells, also known as T-lymphocytes, are a type of lymphocyte that plays a crucial role in the immune response, particularly in cell-mediated immunity.

2. **Understand the Lifespan of Lymphocytes**: Recognize that most lymphocytes, including T-cells, have varying lifespans. While many lymphocytes are short-lived, some can survive much longer.

3. **Differentiate Between T-cells and Other Lymphocytes**: Note that T-cells can be distinguished from other types of lymphocytes, such as B-cells and natural killer cells, primarily by the presence of T-cell receptors on their surface.

4. **Consider the Lifespan Options**: The question provides several options for the lifespan of T-cells:
- 4 to 5 days
- 4 to 5 weeks
- 4 to 5 months
- 4 to 5 years

5. **Analyze the Lifespan of T-cells**: According to the information, while most lymphocytes have a lifespan of about a week to a few months, some T-cells can live for several years.

6. **Select the Correct Answer**: Based on the analysis, the correct lifespan for T-cells is 4 to 5 years.

### Final Answer:
The lifespan of T-cells is **4 to 5 years** (Option D).