Where does UML explicitly intend String Expression elements to be used?

Where does UML explicitly intend String Expression elements to be used?
A . as (he ValueSpecifications for the nameExpressions of ParameterableElements within Template specifications
B . as the model the author chooses for the specification of custom dynamically-generated names for any NamedElement
C . whenever an OpaqueExpression form of a ValueSpecification needs to specify an expression that operates on String instances
D . The specification has no metaclass StnngExpression and so no use of StringExpression is explicitly intended.

View Answer

Answer: D

Explanation:

In UML, ValueSpecifications are used to specify the value of an element. The UML 2 Specification does not define a metaclass named StringExpression. Instead, it provides a metaclass named OpaqueExpression, which can be used when an expression is written in a language that is not directly interpretable by the model. Since there is no metaclass called StringExpression in the UML 2 Specification, there is no explicitly intended use for it within the UML metamodel. The absence of this metaclass suggests that any use of a concept called "StringExpression" would not conform to standard UML 2 practices and would likely be part of an extension or profile, not the core UML metamodel.