Which of the following are the properies of acquired immunity ?

Options

A. Specificity
B. Diversity
C. memory
D. All of the above

Answer

To answer the question regarding the properties of acquired immunity, we will analyze each of the options provided: specificity, diversity, memory, and all of the above.

### Step-by-Step Solution:

1. **Understanding Acquired Immunity**:
- Acquired immunity, also known as adaptive immunity, is a type of immunity that develops after exposure to a specific pathogen. It is characterized by the ability to recognize and remember specific pathogens.

2. **Analyzing Specificity**:
- Acquired immunity is highly specific. This means that the immune response is tailored to target specific antigens. For example, if the body is exposed to a virus, the immune system will produce antibodies specifically against that virus.

3. **Analyzing Diversity**:
- Acquired immunity exhibits diversity. The immune system can produce a wide range of antibodies and immune cells that can recognize and respond to many different pathogens. This diversity allows the immune system to adapt to new threats.

4. **Analyzing Memory**:
- One of the key features of acquired immunity is memory. After an initial exposure to a pathogen, the immune system creates memory cells that "remember" the specific antigens. If the same pathogen invades again, these memory cells enable a faster and more effective immune response.

5. **Conclusion**:
- Given the analysis, all the properties mentioned (specificity, diversity, and memory) are indeed characteristics of acquired immunity. Therefore, the correct answer to the question is "all of the above."

### Final Answer:
The properties of acquired immunity include specificity, diversity, and memory. Therefore, the correct option is **all of the above**.

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