What is defined as the set of inputs of a function?

The correct choice defines the set of inputs for a function, known as the domain. The domain consists of all the values that can be used as input for the function, ensuring that each input produces a valid output according to the function's definition. Understanding the domain is crucial because it specifies the limitations or requirements of the function's inputs.

For example, if you have a function that involves division, the domain must exclude any input that would result in division by zero, as this is undefined.

The range, which is another term related to functions, refers to the set of possible outputs that can result from using the values in the domain, but it does not define the inputs. The output itself is simply the result of applying the function to an input, while the term "Function Set" is not a standard term used in relation to functions within mathematics.