Which of the following has revolutionised the discipline of biotechnology

Options

A. Restriction endonucleases
B. Discovery of DNA structure
C. Recombinant DNA
D. All the these

Answer

**Step-by-Step Solution:**

1. **Understanding Biotechnology**: Begin by defining biotechnology. It is a field that involves the use of living organisms or their systems to develop or create products, often through genetic engineering.

2. **Identifying Key Components**: Recognize the key components that have revolutionized biotechnology:
- **Restriction Endonucleases**: These are enzymes that cut DNA at specific sequences, often referred to as "molecular scissors." They are crucial for manipulating DNA.
- **Discovery of DNA Structure**: Understanding the double helix structure of DNA is fundamental for studying genetic material and its functions.
- **Recombinant DNA Technology**: This involves combining DNA from different sources to create new genetic combinations that are of value in research, medicine, and agriculture.

3. **Evaluating Options**:
- **Option 1**: Restriction Endonucleases - Important for cutting DNA.
- **Option 2**: Discovery of DNA Structure - Essential for understanding DNA.
- **Option 3**: Recombinant DNA - Critical for genetic engineering.
- **Option 4**: All the Above - This option suggests that all the previous components have contributed to the revolution in biotechnology.

4. **Conclusion**: Since all three components (restriction endonucleases, discovery of DNA structure, and recombinant DNA technology) have played significant roles in advancing the field of biotechnology, the correct answer is **Option 4: All the Above**.

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