What is a potential effect of changing the scale on the y-axis of a chart?

• A. It changes the underlying data values.
• B. It can make differences between data groups seem more drastic than they actually are.
• C. It has no effect on interpretation.
• D. It improves the accuracy of the data.

Answer: (B)

Altering the y-axis scale affects how differences are perceived, not the actual data values. By narrowing or widening the plotting range, you change how far apart data points look. This can make differences between groups appear much larger or smaller than they truly are, which can mislead interpretation. The underlying numbers stay the same, so changing the scale doesn’t improve data accuracy, and it does change how the chart is read.