Give an example of disarmed viruses used as vector in animals .

Explanation

### Step-by-Step Solution:

1. **Identify the Type of Virus**: The question asks for an example of disarmed viruses used as vectors in animals. One significant type of virus that fits this description is retroviruses.

2. **Understanding Retroviruses**: Retroviruses are RNA viruses, meaning their genetic material is composed of ribonucleic acid (RNA) instead of deoxyribonucleic acid (DNA). This characteristic is crucial in their function as vectors.

3. **Purpose of Disarming**: Retroviruses can transform normal cells into cancerous cells. To prevent this harmful effect, these viruses are disarmed before being used as vectors. Disarming involves the removal or destruction of disease-causing genes from the virus.

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