Why is a bar graph a useful tool in statistics?

A bar graph is particularly effective in visually comparing different categories, which is why it is the correct answer. By representing each category with a distinct bar, viewers can quickly interpret and compare values associated with each category. The height or length of each bar provides an immediate visual gauge of the relative sizes, making it easier to identify patterns, differences, and similarities across categories at a glance.

While other forms of data representation serve important purposes, they do not fulfill the specific function of quickly comparing categories as effectively as a bar graph does. For instance, line graphs are generally more suited for displaying trends over time, while histograms are better for showing data distributions. Bar graphs excel in their simplicity and clarity for categorical comparisons, making them a staple tool in data visualization and analysis.