Which technique is used to determine the area of origin at a crime scene?

• A. Base line
• B. Stringing
• C. Triangulation
• D. Polar coordinates

Answer: (B)

Determining the area of origin relies on tracing the direction of bloodstains back to where they came from. The technique of stringing is the best fit because it directly turns those directional clues into visual lines you can extend across the scene. By aligning strings with the long axis or projected trajectory of multiple stains and extending those lines inward, the strings intersect near the source. The point of convergence reveals the likely area from which the blood originated, often giving a sense of height and angle when combined with more stains.

Other mapping methods aren’t as directly tied to reconstructing a blood trajectory. Baseline helps establish a reference axis for measuring distances, while triangulation and polar coordinates are about locating points from fixed references on a map or plan. They’re useful for overall scene layout, but they don’t inherently translate the directionality of stains into a convergent origin like stringing does.