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Forensic scientists have to work often w...

Forensic scientists have to work often with extremely small samples of DNA obtained from the hair or other sources of suspected criminals. However, it is possible to produce DNA 'fingerprint from these small samples by using

A

gene gun

B

gene cloning

C

polymerase chain reaction

D

genetically engineered microorganisms

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To solve the question regarding how forensic scientists can produce DNA fingerprints from extremely small samples of DNA, we can follow these steps: ### Step-by-Step Solution: 1. **Understanding the Context**: Forensic scientists often work with very small samples of DNA, which may come from sources like hair or other biological materials. The challenge is to analyze these tiny amounts of DNA effectively. 2. **Identifying the Techniques**: The question provides four options: - A) Gene gun - B) Gene cloning - C) Polymerase chain reaction (PCR) - D) Genetically engineered microorganisms 3. **Analyzing the Options**: - **Gene Gun**: This is a method used to introduce DNA into cells but is not specifically used for amplifying DNA from small samples. - **Gene Cloning**: This involves creating copies of a specific gene but does not directly apply to analyzing small DNA samples for forensic purposes. - **Polymerase Chain Reaction (PCR)**: This is a technique specifically designed to amplify small segments of DNA, making it possible to analyze even tiny amounts of genetic material. - **Genetically Engineered Microorganisms**: While these can be used in various biotechnological applications, they are not directly related to the amplification of small DNA samples. 4. **Selecting the Correct Technique**: Given the need to amplify DNA from small samples, the most suitable technique is the Polymerase Chain Reaction (PCR). This method allows scientists to create millions of copies of a specific DNA segment, making it easier to analyze and create a DNA fingerprint. 5. **Conclusion**: The correct answer to the question is **C) Polymerase chain reaction**. This technique is essential for producing DNA fingerprints from small samples.
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