Which chart type is used to represent the proportional measurement of categorical values with horizontal or vertical bars?

A bar chart is the appropriate choice for representing proportional measurements of categorical values using horizontal or vertical bars. This type of chart effectively displays the comparison between different categories, allowing viewers to easily interpret relative sizes and relationships among the data. Each bar corresponds to a category, with the length or height of the bar reflecting the value associated with that category.

In contrast, a histogram specifically represents the distribution of numerical data across continuous intervals or bins rather than categorical values. A pie chart is designed to show parts of a whole by illustrating the proportional contribution of each category, but it does not use bars for representation. A line graph is best used for displaying trends over time, effectively illustrating the relationship between variables through points connected by lines, rather than comparing distinct categorical values.

Thus, the bar chart is the most effective visualization for comparing categories proportionally, as it allows for easier interpretation of differences in magnitude across multiple groups.