What is defined as an instance of a class?

An instance of a class is defined as an object. In object-oriented programming, a class serves as a blueprint for creating objects, which represent individual instances of that class. Each object can hold its own unique data and behavior defined by that class.

When you create an object from a class, you are essentially instantiating that class, meaning you are creating a specific realization of the class which can interact with the program according to the methods and attributes defined within the class. This encapsulates both data (attributes) and functions (methods) that operate on the data, allowing for organized and modular programming.

The other choices do not fit the definition of an instance of a class. A method refers to a function that belongs to a class and describes behaviors of the class's objects. A function is a block of code that performs a specific task and does not inherently possess any class structure. A variable is a storage location in programming that holds data values but is not an instance on its own. Therefore, the term "object" is the most accurate representation of an instance of a class.