A genetic disorder can be cured through

Options

A. rDNA technology
B. embryo transfer
C. gene therapy
D. all of these

Explanation

**Step-by-Step Solution:**

1. **Understanding Genetic Disorders**: Genetic disorders are caused by defects in genes, which can occur due to various changes in the DNA sequence, such as addition, deletion, substitution, or insertion of nucleotides. These changes can lead to malfunctioning proteins or enzymes that are crucial for normal bodily functions.

2. **Evaluating the Options**:
- **Option 1: rDNA Technology**: This technology involves manipulating DNA by combining genetic material from two different organisms to create recombinant DNA. While this is a powerful tool in biotechnology, it is not specifically designed to correct genetic defects in individuals.
- **Option 2: Embryo Transfer**: This is an assisted reproductive technique primarily used to help infertile couples conceive. It does not address the underlying genetic defects in embryos.
- **Option 3: Gene Therapy**: This method involves correcting or replacing defective genes responsible for disease development. It targets the genetic defect directly and can potentially cure genetic disorders by restoring normal function to the affected genes.

3. **Conclusion**: Based on the evaluation of the options, gene therapy is the most appropriate method for curing genetic disorders. It directly addresses the genetic defects that cause these disorders.

4. **Final Answer**: A genetic disorder can be cured through **gene therapy**.

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