The type of immunity that develops as a result of natural exposure to an antigen in the environment

Options

A. natural innate immunity
B. naturally acquired passive immunity
C. nonspecific immunity
D. naturally acquired active immunity

Answer

### Step-by-Step Solution:

1. **Understanding Antigens**: Antigens are substances that can induce an immune response in the body. They are typically found on the surface of pathogens like viruses and bacteria.

2. **Immune Response**: When an antigen enters the body, the immune system recognizes it as foreign and responds by producing antibodies. Antibodies are proteins that specifically target and neutralize the antigens.

3. **Types of Immunity**: Immunity can be classified into two main types: innate immunity (which is present from birth) and adaptive immunity (which develops over time). Adaptive immunity can further be divided into active and passive immunity.

4. **Natural Exposure**: The question specifies "natural exposure to an antigen in the environment." This means that the body encounters the antigen through everyday interactions, such as through infections or environmental exposure.

5. **Naturally Acquired Active Immunity**: When the body is exposed to an antigen naturally (for example, through infection), it mounts an immune response and produces antibodies. This process leads to the development of "naturally acquired active immunity," which provides long-lasting protection against that specific pathogen.

6. **Conclusion**: Therefore, the type of immunity that develops as a result of natural exposure to an antigen in the environment is called "naturally acquired active immunity."

### Final Answer:
The type of immunity that develops as a result of natural exposure to an antigen in the environment is **naturally acquired active immunity**.

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