Which of the following is NOT a built-in data type in Python?

In Python, the built-in data types include integers, booleans, and strings, among others. An integer is a whole number without a fractional component, while a boolean represents one of two values: True or False. A string is a sequence of characters used to represent text.

The term "Decimal," however, refers to a data type that is not built-in but is instead provided by the decimal module in Python. This module offers support for decimal floating-point arithmetic, which is useful for precise arithmetic operations, especially in financial applications. While you can use decimal numbers in Python, the specific Decimal type itself is not considered a built-in data type.

Thus, identifying Decimal as the choice that is not a built-in data type aligns with Python's standard library organization, highlighting the distinction between core data types and those provided by additional modules.