The biochemical procedure used to detect human chorionic gonadotrophin is

Options

A. WIDAL
B. CAT
C. MRI
D. ELISA

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the biochemical procedure used to detect human chorionic gonadotropin (HCG).

2. **Identifying the Options**: The options provided are:
- A) Vidal
- B) CAD
- C) MRI
- D) ELISA

3. **Analyzing Each Option**:
- **A) Vidal**: This is not a recognized method for detecting HCG.
- **B) CAD**: This is not related to HCG detection.
- **C) MRI**: This is an imaging technique and not a biochemical test.
- **D) ELISA**: This stands for Enzyme-Linked Immunosorbent Assay, which is a biochemical method that uses antibodies to detect specific substances.

4. **Understanding ELISA**: ELISA is specifically designed to identify substances like hormones. In the case of HCG, a sample (usually urine) is mixed with monoclonal antibodies that are specific to HCG. If HCG is present, it binds to these antibodies, forming a complex.

5. **Conclusion**: Since ELISA is the only method among the options that is used for the detection of HCG, the correct answer is option D, ELISA.

**Final Answer**: The biochemical procedure used to detect human chorionic gonadotropin is D) ELISA.

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