Final answer:
Three-year-old Molly's cognitive ability to predict the arrival of the mail carrier because it is daytime is an example of 'theory of mind' (TOM), a developmental stage where children understand that others have separate thoughts and beliefs.
Step-by-step explanation:
The type of thinking demonstrated by three-year-old Molly, as she predicts the arrival of the mail carrier based on the time of day, is indicative of a cognitive development known as theory of mind (TOM). Children between the ages of 3 and 5 begin to understand that people have their own thoughts, feelings, and beliefs which may differ from their own. This development allows them to interpret and predict others' behaviors. For instance, Molly understands that the mail carrier has a routine that leads to the arrival during the daytime. False belief tasks, like the crayon box experiment mentioned, are one method used to determine if a child has acquired TOM.