Final answer:
The correct option is c. Graphs, such as bar graphs and pie charts, are valuable for visually expressing equations and for comparing quantities or showing proportions within a whole, which allows for a quick and clear understanding of complex information.
Step-by-step explanation:
Tables and graphs are instrumental in conveying complex information in a digestible format. Graphs in particular are helpful in two distinct ways. First, they can express equations visually, allowing for a clearer understanding of the mathematical relationships. This can be illustrative when showing how changing one variable affects another.
Bar graphs are equally powerful and are specifically beneficial when it comes to comparing quantities. For example, when studying demographic information like the populations of different countries, bar graphs can not only demonstrate the relative sizes of these populations but also delve into subgroup breakdowns within each population. This multi-layered approach to data presentation helps to better analyze and understand the data.
Pie charts are another type of graph that is particularly useful when emphasizing proportions within a whole. By representing categories as wedges of a circle, they show the percentage distribution of various parts, making it simple to understand the composition of a dataset at a glance.