A FunctionBehavior in UML is a specialized form of behavior that specifies a function that, when executed, yields results influenced only by its input arguments and its internal attributes, without any side effects (e.g., altering global variables or I/O operations). This makes it stateless. Among the options provided:

A involves I/O operations which are not covered under FunctionBehavior as it implies side effects.

B deals with environmental inputs and actuator control, not just function computation.

C could be considered but implies a state change which again might involve side effects, depending on the implementation.

D purely involves calculation based on input parameters, which fits the definition of FunctionBehavior perfectly, as it is a stateless computation.

E is incorrect because UML indeed includes the concept of FunctionBehavior.

UML Specification, Section on Behaviors

Further details on FunctionBehaviors can be found in the UML 2.5 Documentation under the Classification and Behaviors sections.