Transgenic animals are

Options

A. Animals whose DNA is manipulated to possess and express an extra (foreign) gene
B. Animals whose RNA is manipulated to possess and express an extra (foreign) gene
C. Animals whose both DNA and RNA are manipulated to possess and express an extra (foreign) gene.
D. None of the above

Explanation

**Step-by-Step Solution:**

1. **Understanding Transgenic Animals**: Transgenic animals are defined as animals whose genetic makeup has been altered using biotechnology. This alteration typically involves the introduction of a foreign gene into their genome.

2. **Manipulation of DNA**: The primary method of creating transgenic animals involves manipulating their DNA. This means that a foreign gene is inserted into the animal's DNA, allowing it to express new traits or characteristics that it would not normally possess.

3. **Options Analysis**:
- **Option 1**: "Animal whose DNA is manipulated to possess and express an extra foreign gene." This option correctly describes transgenic animals, as it focuses on the manipulation of DNA.
- **Option 2**: "Animal whose RNA is manipulated to possess and express an extra foreign gene." This option is incorrect because transgenic animals are primarily defined by DNA manipulation, not RNA.
- **Option 3**: "Animal whose both DNA and RNA is manipulated to possess and express an extra foreign gene." This option is also incorrect for the same reason; transgenic status is based on DNA modification.
- **Option 4**: "None of the above." This option is incorrect since option 1 is a valid description.

4. **Conclusion**: Based on the definitions and analysis of the options, the correct answer is **Option 1**: "Animal whose DNA is manipulated to possess and express an extra foreign gene."

**Final Answer**: Option 1

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