Can the font used in a packaged product affect our perception of the product’s healthiness? It was hypothesized that use of a natural font, which looks more handwritten and tends to be more slanted and curved, would lead to a higher perception of product healthiness than an unnatural font. Two fonts, Impact and Sketchflow Print, were used. These fonts were shown in a previous study to differ in their perceived naturalness, but otherwise were rated similarly on factors such as readability and likeability. Images of two identical packages differing only in the font used were presented to the subjects. Participants read statements such as “This product is healthy”/natural/wholesome/organic, and they rated how much they agreed with the statement on a seven-point scale with “1” indicating strongly agree and “7” indicating strong disagreement. Each subject’s responses were combined to create a perceived healthiness score. The researcher had 100 students available to serve as subjects.(a) What is the explanatory variable?