Which one of the following technique made it possible to genetically engineer living organisms

Options

A. Hybridization
B. Recombinant DNA techniques
C. X-ray diffraction
D. Heavier isotope labelling

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the technique that enables the genetic engineering of living organisms. This requires knowledge of various biotechnological techniques.

2. **Evaluating the Options**:
- **Option A: Hybridization** - This is a process where two different species or varieties are crossed to produce hybrids. While it is important in breeding, it does not involve direct genetic manipulation.
- **Option B: Recombinant DNA techniques** - This involves combining DNA from different organisms to create new genetic combinations. It is a fundamental technique in genetic engineering.
- **Option C: X-ray diffraction** - This technique is used to study the structure of molecules but does not involve genetic manipulation.
- **Option D: Heavier isotope labeling** - This is a method used in tracing biochemical pathways but is not a technique for genetic engineering.

3. **Identifying the Correct Technique**: Among the options, recombinant DNA techniques (Option B) is the only one that directly relates to altering the genetic material of organisms, thus enabling genetic engineering.

4. **Conclusion**: The technique that made it possible to genetically engineer living organisms is **recombinant DNA techniques**.

**Final Answer**: Option B: Recombinant DNA techniques.

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