Which chart type would best show how values change over time?

• A. Pie chart.
• B. Histogram.
• C. Line chart.
• D. Vertical bar chart.

Answer: (C)

When you want to show how values change over time, you need a visualization that preserves the order of observations and highlights trends: a line chart. It plots each time point with its value and connects them with a line, making the pattern of increase, decrease, or cycles easy to see. A pie chart only shows parts of a whole at a single moment, not changes over time. A histogram focuses on the distribution of values, not their sequence. A vertical bar chart can compare values across categories or individual time points, but it doesn’t convey continuous progression and trends as clearly as a line chart. So for illustrating changes over time, the line chart is the best choice.