Which of the following is not a special feature of specific immunity?

Options

A. specificity
B. diversity
C. Memory
D. PMNL

Answer

To determine which of the following is not a special feature of specific immunity, we need to understand the characteristics of specific immunity.

### Step-by-Step Solution:

1. **Understand Specific Immunity**: Specific immunity, also known as adaptive immunity, is a part of the immune system that is tailored to recognize and respond to specific pathogens. It develops over time and has distinct features.

2. **Identify Features of Specific Immunity**:
- **Specificity**: This means that specific immunity can recognize and target specific pathogens or antigens. Each immune response is tailored to a particular pathogen.
- **Diversity**: The immune system can generate a vast array of antibodies and T-cell receptors that can recognize an almost infinite number of antigens.
- **Memory**: After an initial exposure to a pathogen, the immune system creates memory cells that allow for a faster and more effective response upon subsequent exposures to the same pathogen.

3. **Contrast with Innate Immunity**: Innate immunity is the body's first line of defense and includes barriers like skin and mucous membranes, as well as immune cells that respond to pathogens in a generic way. It does not have the features of specificity, diversity, or memory.

4. **Determine the Incorrect Feature**: Since the question asks for a feature that is NOT part of specific immunity, we can conclude that any characteristic that does not include specificity, diversity, or memory would be the answer.

5. **Conclusion**: The feature that is not a part of specific immunity is likely to be a characteristic of innate immunity or a general immune response that lacks specificity.

### Final Answer:
The feature that is not a special feature of specific immunity is a characteristic of innate immunity.