A 5-Whys analysis is said to complement which problem-solving diagram?

• A. Fishbone (Ishikawa) diagram
• B. Flowchart
• C. Scatter plot
• D. PERT chart

Answer: (A)

Root-cause analysis is the idea, and the 5 Whys method digs deeper by repeatedly asking why to uncover underlying causes. The Fishbone (Ishikawa) diagram is a visual tool that organizes potential causes into categories, providing a structured way to map those root causes. When you apply 5 Whys to identify deeper drivers and then lay them out on the fishbone, you connect a problem to its fundamental sources in a clear, multi-branch view. This pairing makes it easier to see how different factors contribute and to prioritize corrective actions. The other diagrams serve different purposes—flowcharts map process steps, scatter plots show relationships between variables, and PERT charts model project timing—so they don’t align as naturally with root-cause exploration.