Which of the following data types is NOT supported in ActionScript 3.0?

In ActionScript 3.0, the data types that are supported include Number, String, and Boolean, but there is no dedicated Integer data type. Instead, numbers in ActionScript 3.0 are represented as floating-point numbers. This means that the representation of numeric values encompasses both whole numbers and decimal values using the Number data type.

While there are various arithmetic operations performed with integer values, they are all executed within the Number type. When working with values that might typically be integers in other programming languages, ActionScript treats them as floating-point numbers, which can store decimal values but provide dynamic allocation.

The choice of having a default Number type means that developers do not need to declare separate data types for integer values, simplifying code and ensuring all numeric values are handled under a uniform standard. This distinction leads to the conclusion that Integer is not a recognized data type in ActionScript 3.0, affirming that the correct answer is the option that identifies it as unsupported.