Which of the following statements about transgenic animals is/are false
(i) Transgenic animals are designed to study how genes are regulated
(ii) They are specially made to serve as models for human diseases
(iii) Transgenic cow Rosie was created to produce human protein `alpha`-1 antitrypsin
(iv) Transgenic mice are used to test the safety of vaccines

Options

A. iii only
B. I and iii only
C. ii only
D. ii and iii only

Answer

To determine which statements about transgenic animals are false, let's analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement (i): Transgenic animals are designed to study how genes are regulated.**
- This statement is **true**. Transgenic animals have modified genes that allow researchers to study gene regulation and its effects on physiology and disease.

2. **Statement (ii): They are specially made to serve as models for human diseases.**
- This statement is also **true**. Transgenic animals are often created to mimic human diseases, which helps in understanding disease mechanisms and testing treatments.

3. **Statement (iii): Transgenic cow Rosie was created to produce human protein alpha-1 antitrypsin.**
- This statement is **false**. Transgenic cow Rosie was actually created to produce the human protein alpha-lactalbumin, not alpha-1 antitrypsin. Therefore, this statement is incorrect.

4. **Statement (iv): Transgenic mice are used to test the safety of vaccines.**
- This statement is **true**. Transgenic mice are commonly used in research to test the safety and efficacy of vaccines and other medical treatments.

### Conclusion:
Based on the analysis, the only false statement is **(iii)**. Thus, the answer to the question is that the false statement about transgenic animals is:

**Answer: (iii) only**

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