Which of the following is NOT a data type?

The choice identified as correct reflects a common understanding of data types used in programming and data management. In many contexts, “Decimal” is not classified as a standalone type but rather falls under the broader category of numeric types that can include various representations like integers, floats, or doubles, depending on the language or framework in use.

On the other hand, Boolean, String, and Character are all clearly defined data types. A Boolean represents a truth value with only two possible states: true or false. A String is a sequence of characters, often used to represent text data, while a Character typically refers to a single unit of text, representing an individual letter or symbol. These distinctions highlight that "Decimal" does not exist as a type in the same definitive way; instead, it is more accurately described as a specific form of numeric value rather than a distinct type.