Enumeration literals in UML are used within an enumeration to define a set of named constants. According to the UML specification:
A: This statement is correct. Enumeration literals are indeed immutable, which means once they are defined within an enumeration, their values cannot be changed.
B: Enumeration literals cannot be anonymous; they must be named so that they can be referenced unambiguously within the model.
C: Enumeration literals can be compared for equality. In fact, this is one of their primary uses, to allow for comparison between different values of an enumerated type to determine if they are the same.
D: Enumeration literal names must be unique within their enumeration. They cannot appear more than once as this would cause ambiguity in references to the literals.
The most accurate statement according to the UML 2 Foundation specification isA: EnumerationLiterals are immutable.