Final answer:
The mental image or best example of a category is a prototype, while a heuristic is a method for sorting items into categories quickly by using mental shortcuts.
Step-by-step explanation:
The best example or mental image of a category is known as a prototype. When thinking about a category, like 'dog', the mental image that pops up (such as a Golden Retriever) is the prototype you associate with that category. A quick and easy method for sorting items into categories is by using a heuristic, which is a general problem-solving framework or mental shortcut that helps people make quick decisions. However, it's important to note that while heuristics save time, they may not always lead to rational decisions.
On the other hand, a schema is a mental construct that involves a cluster of related concepts, which helps in organizing information efficiently and guides behavior in various scenarios.