Which graph is described as a frequency distribution where data points are connected by straight lines?

• A. Frequency polygon (line graph)
• B. Stem-and-leaf plot
• C. Box-plots
• D. Histogram

Answer: (A)

To visualize how often data occur across different ranges, you plot the frequency for each class interval at its midpoint and then connect those points with straight lines. This creates a continuous line that outlines the distribution, called a frequency polygon (also described as a line graph). It’s the line-graph version of a histogram, which uses bars instead of connecting lines. The other options serve different purposes: a stem-and-leaf plot shows actual data values in a compact list form, a box plot summarizes spread and quartiles without tracing a line across intervals, and a histogram uses adjacent bars to display frequencies but does not form a connected line.