Expand 'ELISA'. Why is this method preferred over conventional methods of diagnosis of diseases ?

Explanation

### Step-by-Step Solution:

1. **Expand 'ELISA':**
- The full form of ELISA is **Enzyme-Linked Immunosorbent Assay**.

2. **Understanding the Principle of ELISA:**
- ELISA is based on the principle of **antigen-antibody reaction**. It utilizes the specificity of antibodies to detect the presence of antigens (such as proteins, peptides, hormones, or antibodies) in a sample.

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