The techniques that serve the purpose of early diagosis :-

Options

A. Polymerase chain Reaction
B. ELISA
C. Recombinant DNA technology
D. All of the above

Answer

### Step-by-Step Text Solution:

1. **Understanding Early Diagnosis**: Early diagnosis refers to the detection of diseases at an initial stage, which is crucial for effective treatment and management.

2. **Identifying Techniques for Early Diagnosis**: The question asks for techniques that aid in early diagnosis. The options provided are:
- Polymerase Chain Reaction (PCR)
- Allazza
- Recombinant DNA technology
- All of the above

3. **Exploring Polymerase Chain Reaction (PCR)**:
- PCR is a technique used to amplify nucleic acids (DNA or RNA).
- By increasing the concentration of the target nucleic acid, PCR allows for the detection of pathogens, which is essential for early diagnosis.

4. **Understanding Allazza**:
- Allazza is an enzyme-linked immunoassay (ELISA) technique.
- It is based on the antigen-antibody reaction, which helps in detecting specific proteins or antigens associated with diseases.

5. **Exploring Recombinant DNA Technology**:
- Recombinant DNA technology involves combining DNA from different sources to create new genetic combinations.
- This technology can be used to diagnose diseases by inserting a gene of interest into a suitable host organism, which can then produce proteins that indicate the presence of a disease.

6. **Conclusion**: Since all three techniques (PCR, Allazza, and Recombinant DNA technology) serve the purpose of early diagnosis, the correct answer is "All of the above."

### Final Answer:
**All of the above.**

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