A pie chart is best used to communicate which type of information?

A pie chart is particularly effective in communicating the comparative size of different categories, as it visually represents parts of a whole. When using a pie chart, each slice of the pie corresponds to a specific category and its proportion relative to the entire dataset. This makes it easy for viewers to grasp how large or small each category is in comparison to others.

Option C, while it presents a specific scenario, does not align with the primary function of a pie chart as effectively as the comparative size of categories does. Pie charts are most suitable for showing distribution among components, such as the percentage of total responses or sales from different products, illustrating how each part contributes to the whole.

In contrast, trends over time require a more linear representation, making line graphs more appropriate. Similarly, steps in a process are better depicted through a flowchart or a series of diagrams that outline sequential actions. While the number of native speakers of languages may suggest comparison, it is in the context of showing overall distribution that a pie chart excels, reinforcing the idea of proportional representation among categories.