An example of gene therapy is

Options

A. production of injectable hepatitis B vaccine
B. production of vaccines in food crops like potatoes which can be eaten
C. introduction of gene for adenosine deaminase in persons suffering from Severe Combined Immuno Deficiency (SCID)
D. production of test tube babies by artificial insemination and implanation of fertilized eggs

Answer

**Step-by-Step Solution:**

1. **Understanding Gene Therapy**:
- Gene therapy involves the introduction, removal, or alteration of genetic material within a person's cells to treat or prevent disease. It is primarily used for genetic disorders.

2. **Identifying Genetic Disorders**:
- Genetic disorders are diseases caused by abnormalities in an individual's DNA. Examples include severe combined immunodeficiency (SCID), cystic fibrosis, and hemophilia.

3. **Examples of Gene Therapy**:
- The question asks for an example of gene therapy. We need to differentiate between gene therapy and other biotechnological applications like vaccine production.

4. **Evaluating Options**:
- The options provided include:
- A) Production of injectable hepatitis B vaccine (this is a vaccine production, not gene therapy).
- B) Production of vaccines in food crops like potatoes (this is genetic engineering in agriculture, not gene therapy).
- C) Introduction of the gene for adenosine deaminase in a person suffering from severe combined immunodeficiency (this is a direct application of gene therapy).
- D) Production of test tubes by artificial insemination (this is a reproductive technique, not gene therapy).

5. **Selecting the Correct Answer**:
- The correct answer is C) Introduction of the gene for adenosine deaminase in a person suffering from severe combined immunodeficiency. This is a classic example of gene therapy as it involves correcting a genetic defect to improve the patient's immune system.

**Final Answer**: C) Introduction of the gene for adenosine deaminase in a person suffering from severe combined immunodeficiency.

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