Study of interaction of antigen and antibody in blood is

Options

A. serology
B. nephrology
C. angiology
D. haematology

Answer

To solve the question regarding the study of the interaction of antigen and antibody in blood, we will analyze each of the provided options step by step.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the term that describes the study of the interaction between antigens and antibodies in the blood.

2. **Analyzing the Options**:
- **Nephrology**: This term refers to the study of the nephron, which is the functional unit of the kidney. It is not related to blood or the interaction of antigens and antibodies.
- **Angiology**: This term pertains to the study of blood vessels, including arteries, veins, and capillaries. Again, this does not relate to the study of antigens and antibodies.
- **Hematology**: This is the study of blood. While it involves various components of blood, it does not specifically focus on the interaction between antigens and antibodies.
- **Serology**: This term refers to the study of blood serum, which is the liquid portion of blood that remains after coagulation. Importantly, serum contains antibodies, and the study of serology involves examining the interactions between antigens (foreign substances) and antibodies (immune proteins).

3. **Identifying the Correct Answer**: Based on the definitions and focus of each term, the correct answer to the question is **serology**, as it specifically deals with the interaction of antigens and antibodies in the blood.

### Final Answer:
The study of the interaction of antigen and antibody in blood is known as **serology**.

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