Final answer:
Lavonne could be comparing different aspects of the two data sets using dot plots, such as their ranges or measures of central tendency, but without the actual plots, we cannot definitively select a single option.
Step-by-step explanation:
Lavonne is comparing two sets of data using dot plots that share the same number line. From the provided options, it is not certain which description applies without viewing the actual plots. However, if we infer from typical reasons to compare dot plots on the same number line, it is likely that Lavonne is either looking at how the measures of central tendency differ between the two data sets or how their distributions might differ. For instance, if one graph has a wider spread of data points causing a larger range, and the other is more tightly clustered, this would suggest that the data sets have different ranges (option c). On the other hand, if data points on the dot plots are organized differently around the central point, it might imply different measures of central tendency (option b).