This is likely an example of a referential delusion.
Explanation:
Schizophrenia is a mental disorder characterized primarily by its hallucinations and delusions.
Hallucinations are <em>distorted perceptions of reality</em>, which are perceived thanks to the senses, such as <em>auditory or visual</em> hallucinations, for example.
Delusions are fake beliefs the individual has.
In this case, Sally believes there's a special meaning for her in a billboard. This is known as a referential delusion, which is characterized by an individual believing that something from the environment is directed specifically for them, such as seeing hidden messages in the television, for example.
While a market economy has many advantages, such as fostering innovation, variety, and individual choice, it also has disadvantages, such as a tendency for an inequitable distribution of wealth, poorer work conditions, and environmental degradation.
