During the first week of April, the ChefZ cooking pan was out of stock at Online Retailer X. Day 1 shoppers are those shoppers who came to Online Retailer X's website seeking a ChefZ cooking pan. For each of the first 3 days of that week, the graph shows the subsequent behavior of all the Day 1 shoppers who visited Online Retailer X's website seeking ChefZ. Shoppers who came to the website and purchased a different item in lieu of ChefZ paid an average of 25% more for the item.
From each drop-down menu, select the option that creates the most accurate statement based on the information provided.
Boreal owls range over a much larger area than do other owls of similar size. Scientists have hypothesized that it is scarcity of prey that leads the owls to range so widely. This hypothesis would be hard to confirm directly, since it is not possible to produce a sufficiently accurate count of the populations of small mammals inhabiting the forests where boreal owls live. Careful study of owl behavior has, however, shown that boreal owls do range over larger areas when they live in regions where food of the sort eaten by small mammals is comparatively sparse. This indicates that the scientists' hypothesis is not sheer speculation.
In the argument given, the two boldfaced portions play which of the following roles?