Minute quantity of hormones & steroid are detected by :

Options

A. Electrophoresis
B. Radio immunoassay
C. Electro encephalogram
D. Fractional analysis

Answer

To solve the question "Minute quantity of hormones & steroids are detected by:", we need to analyze the options provided and understand the techniques mentioned.

### Step-by-Step Solution:

1. **Understanding the Options**:
- **A. Electrophoresis**: This technique is primarily used for separating macromolecules like DNA, RNA, or proteins based on their size and charge. It is not specifically designed for detecting minute quantities of hormones or steroids.

- **B. Radioimmunoassay (RIA)**: This is a sensitive laboratory technique that uses radioactively labeled substances to measure the concentration of antigens (such as hormones) in a sample. It is particularly effective for detecting minute quantities of hormones and steroids in biological fluids.

- **C. Electroencephalogram (EEG)**: This test measures electrical activity in the brain using electrodes placed on the scalp. It is not related to hormone or steroid detection.

- **D. Fractional Analysis**: This is a mathematical approach used to model biological processes but does not specifically pertain to the detection of hormones or steroids.

2. **Identifying the Correct Answer**:
- Among the options, Radioimmunoassay (B) is specifically designed to detect low concentrations of hormones and steroids, making it the most suitable choice for this question.

3. **Conclusion**:
- Based on the analysis, the correct answer to the question is **B. Radioimmunoassay**.

### Final Answer:
**B. Radioimmunoassay**

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