Crowdly

Data, workflow, and testing

Behaviors and relationships

Only UI and controller

A use-case diagram shows an actor interacting with multiple use cases. Which interpretation is MOST correct?

The actor has multiple goals in the system

The actor is a system component

The actor must execute all use cases sequentially

The use cases are dependent

Which of the following scenarios clearly illustrates visibility control in UML?

A subclass cannot access a private attribute

A diagram hides attributes

A class is abstract

Two classes do not communicate

You observe that a sequence diagram includes a fragment marked alt. What does it represent?

Optional execution

Parallel flows

Looping behavior

Alternative flows based on conditions

A package diagram shows Package A depends on Package B. What is the best interpretation?

B invokes A

Classes in A may use classes in B

A contains B

A inherits functionality from B

A system models “ReportGenerator” as an interface with multiple implementations. What OO motivation does this serve?

Improve performance

Ensure only one class generates reports

Avoid overloading

Allow dependency inversion and flexible substitution

A designer uses CRC cards and identifies an operation that belongs to no class. Most likely issue?

A new class should be created

The operation must be removed

Operation belongs to the controller layer

The system needs an interface

Which is MOST likely represented as a swimlane?

A decision rule

A role or department in workflow

A dynamic state

A class

A designer wants to model a system that reacts differently based on time-of-day (e.g., “Night Mode,” “Day Mode”). Which model is suited?

Statechart with timed events

Sequence diagram

Class diagram

Use case diagram

A state transitions to itself on receiving the same event repeatedly. Which scenario is MOST accurate?

Infinite loop is guaranteed

UML prohibits self-transitions

The event represents a retry or validation

The model is incorrect