DFD (Data Flow Diagram) MCQs

1. What is the primary purpose of a Data Flow Diagram (DFD)?

o A) To represent the system’s structure
o B) To show the flow of data within a system
o C) To describe user interface design
o D) To model object-oriented systems
o Answer: B
2. Which symbol is used to represent a process in a Data Flow Diagram?
o A) Circle or Rounded Rectangle
o B) Square
o C) Open-ended arrow
o D) Double circle
o Answer: A
3. In a Level 0 DFD, what represents external entities that interact with the system?
o A) Processes
o B) Data stores
o C) External entities
o D) Data flows
o Answer: C
4. Which of the following is NOT typically represented in a Data Flow Diagram?
o A) Data stores
o B) Processes
o C) Use cases
o D) External entities
o Answer: C
5. What is the correct level of abstraction for a Level 1 DFD?
o A) Detailed decomposition of the system
o B) High-level system overview
o C) Representation of data flow only
o D) Representation of user interfaces
o Answer: A
6. Which of the following is true about a Context-Level DFD?
o A) It shows detailed process flows within the system.
o B) It represents the system as a single process interacting with external entities.
o C) It focuses on data storage within the system.
o D) It identifies all possible data transformations.
o Answer: B
7. What does a data flow between an external entity and a process in a DFD represent?
o A) The storage of data
o B) The flow of data between two systems or subsystems
o C) A function within the system
o D) The execution of an event
o Answer: B
Use Case Diagram MCQs

1. What is the primary purpose of a Use Case Diagram?

o A) To model the flow of data
o B) To represent user interactions with the system
o C) To define the architecture of the system
o D) To describe the sequence of system processes
o Answer: B
2. In a Use Case Diagram, what is an "actor"?
o A) A specific user interface element
o B) An external entity interacting with the system
o C) A process or function within the system
o D) A data store that holds information
o Answer: B
3. Which of the following is typically represented by a "use case" in a Use Case
Diagram?
o A) A specific action or behavior the system must perform
o B) A data flow in the system
o C) A system interface
o D) An external system interacting with the system
o Answer: A
4. What does an "include" relationship in a Use Case Diagram represent?
o A) A dependency between two use cases where one is always performed as part
of another
o B) A condition under which a use case is triggered
o C) A shared resource between two actors
o D) An optional interaction between an actor and a use case
o Answer: A
5. Which of the following does NOT typically appear in a Use Case Diagram?
o A) Actors
o B) Use cases
o C) Relationships (e.g., extend, include)
o D) Data flows
o Answer: D
6. What does the "extend" relationship in a Use Case Diagram represent?
o A) A use case that may be optionally extended or invoked in specific conditions
o B) A use case that includes other use cases unconditionally
o C) A shared resource between actors
o D) A connection between actors and systems
o Answer: A
7. Which of the following actors would be typically represented in a Use Case Diagram
for an ATM system?
o A) Customer
 o B) ATM machine
o C) Bank database
o D) Cash withdrawal process
o Answer: A

Sequence Diagram MCQs

1. What is the primary purpose of a Sequence Diagram?

o A) To model the static structure of the system
o B) To show the dynamic interaction between objects in a time-sequenced manner
o C) To represent the flow of data between processes
o D) To define the system’s architecture
o Answer: B
2. Which of the following elements is typically shown as a vertical dashed line in a
Sequence Diagram?
o A) Actor
o B) Lifeline of an object or participant
o C) Message sent between objects
o D) System boundary
o Answer: B
3. What does an "activation box" in a Sequence Diagram represent?
o A) A message being passed between objects
o B) The time period during which an object is performing an operation
o C) An object that is interacting with another object
o D) A method invocation or function call in the system
o Answer: B
4. What is represented by horizontal arrows between objects in a Sequence Diagram?
o A) Control flow between system components
o B) Messages or method calls passed between objects
o C) Data flow between external entities
o D) State transitions within objects
o Answer: B
5. In a Sequence Diagram, what does a "return message" represent?
o A) A response from one object to another after receiving a message
o B) A process that repeats continuously
o C) The end of an interaction between two objects
o D) A call to an external entity
o Answer: A
6. Which of the following is typically NOT a part of a Sequence Diagram?
o A) Objects/Participants
o B) Lifelines
o C) Messages
o D) Data stores
 o Answer: D
7. In a Sequence Diagram, which symbol represents a message or method call between
two objects?
o A) Solid line with an arrow
o B) Dashed line with a label
o C) Vertical dashed line
o D) Solid rectangle
o Answer: A