Which statement best contrasts sensitivity analysis and scenario analysis and when to use each?

• A. Sensitivity tests multiple variables at once; scenario changes a single driver; use sensitivity for interactions.
• B. Sensitivity tests one variable at a time; scenario changes multiple drivers simultaneously; use both to understand extremes and interactions.
• C. Sensitivity ignores assumptions; scenario uses fixed inputs.
• D. Sensitivity and scenario are interchangeable terms.

Answer: (B)

Sensitivity analysis isolates the effect of changing one input at a time, holding all other assumptions constant, so you can see how much that single variable drives the result. Scenario analysis, by contrast, changes several inputs together to reflect a coherent set of conditions and to reveal how outputs respond to combinations of changes and possible interactions among drivers. Use both to understand extremes and interactions: sensitivity helps identify which inputs matter most on their own, while scenario analysis shows how a mix of changes can push the model into different outcomes and how drivers interact. The statement that sensitivity tests multiple variables at once or that scenario changes a single driver conflicts with how these tools are designed. They’re not interchangeable, and both rely on varying inputs under assumed conditions rather than ignoring them.