Which of the following is NOT an example of a built-in literal value?

A built-in literal value is a fixed value that is defined directly in Appian as part of the language, allowing developers to use them without needing to declare or define them further. The correct choice—zero—is not considered a built-in literal value in Appian's expression language. Instead, true, false, and an empty string are all recognized built-in literal values.

True and false are Boolean literals, used for logical conditions, while the empty string is a string literal that denotes a string with no characters. However, zero, while it represents a numeric value, is often treated as a variable or an expression rather than a literal in the same way the concept applies to Boolean and string values. Therefore, in the context of Appian, zero does not fall under the category of built-in literal values established for the language.