In terms of graphical display, which of the following would be least appropriate for numerical continuous data?

A bar chart is least appropriate for displaying numerical continuous data because it is primarily designed for categorical data. In a bar chart, each bar represents a distinct category, and the height or length of the bar reflects the value or frequency associated with that category. This format does not effectively capture the continuous nature of numerical data, which can take on an infinite number of values within a given range.

In contrast, a box plot provides a visual summary of the distribution of continuous data, including its median, quartiles, and potential outliers. A histogram is ideal for continuous data as it groups the data into intervals (bins) to show the frequency distribution, allowing for a clear understanding of the data's overall shape and variability. Scatter plots are useful for displaying the relationship between two continuous variables, making them appropriate for examining correlations and trends.

Given these roles, a bar chart is not suited to convey the nuances of numerical continuous data, whereas the other graphical displays are specifically designed for that purpose.