Which of the following best describes a histogram?

• A. A histogram uses non-adjacent bars to represent individual data points.
• B. A histogram is a type of pie chart that shows proportions of categories.
• C. A histogram is used to show the relationship between two categorical variables.
• D. A histogram displays the frequency $f$ of data within equal-width intervals using adjacent bars.

Answer: (D)

Verified step by step guidance

1. Understand that a histogram is a graphical representation used to display the distribution of a numerical data set.
2. Recognize that in a histogram, data is grouped into intervals called bins or classes, which are of equal width.
3. Note that the height of each bar in a histogram represents the frequency (or count) of data points within that interval.
4. Observe that the bars in a histogram are adjacent (touching) to each other, indicating the continuous nature of the data intervals.
5. Contrast this with other charts: unlike a bar chart with non-adjacent bars for categorical data, or a pie chart showing proportions, a histogram specifically shows frequency distribution of numerical data using adjacent bars.