A histogram is a graph that shows the frequency distribution of which type of data?

• A. A graph showing frequency distribution of continuous data
• B. A chart for comparing categories
• C. A line graph of time-series data
• D. A pie chart of proportions

Answer: (A)

A histogram is used to show how frequently values occur across a range of numbers for a numeric, continuous variable. The data are grouped into intervals or bins (like 0–10, 10–20, etc.), and the height of each bar tells you how many observations fall into that interval. The key idea is continuity: values can slide within each interval, so the bars are drawn next to each other to reflect that seamless range.

This makes it different from other graphs. A chart designed to compare categories uses separate bars with gaps, reflecting distinct categories rather than a smooth range of values. A line graph of time-series data connects data points over time to reveal trends, not a distribution across value ranges. A pie chart shows proportions of a whole, not frequencies across numeric intervals.

So the best fit is the one that captures distribution of a continuous numeric variable across intervals, which is exactly what a histogram does.