A CEO asks the CIO to show the return on investment (ROI) for mobile technology.

A bar chart is the best choice because the CEO needs a clear, direct comparison of discrete cost categories and their percentage changes after implementing mobile technology. In ROI and economic-impact reporting for health IT, leaders typically want to see how different cost components move in opposite directions (e.g., maintenance down while personnel and communication rise). A bar chart makes these contrasts immediately visible by placing each category on the same scale and displaying positive and negative changes side-by-side, supporting fast executive interpretation and decision-making.

A spider (radar) diagram is better suited for comparing multiple performance dimensions across a common scale (often used in capability or maturity comparisons), but it is less intuitive for conveying simple cost deltas. A scatter plot is used to show relationships or correlation between two variables (e.g., staffing levels vs. throughput), not categorical ROI components. A Pareto chart ranks causes by frequency or magnitude to highlight the “vital few” contributors to a problem; it is most appropriate when analyzing defect types or drivers of cost, not when simply communicating pre/post percentage changes across several budget lines.