When collecting evidence for DNA testing, which collection method is preferred?

• A. Swab
• B. Print
• C. Tape Lift
• D. Scrape

Answer: (A)

Collecting DNA is most effective when the method yields a clean, high-quality sample with minimal disruption to the evidence. A swab fits this goal best because it gathers epithelial cells from a surface or from a person in a non-destructive way, preserving DNA integrity and reducing contamination. Swabs—often sterile and sometimes moistened to improve cell pickup—are standard in forensic workflows, easy to package, and support reliable, repeatable DNA analysis with good yield and clear chain of custody.

Other methods tend to be less ideal for DNA. Prints are focused on restoring fingerprints, not obtaining genetic material. Tape lifts can capture some DNA but also collect surface contaminants and typically provide less consistent DNA yield. Scrapes can damage evidence and introduce more contamination risk, making the resulting DNA data harder to interpret.