Final answer:
A systems programmer should be familiar with all levels of Data Flow Diagrams (DFD), as each level provides different degrees of insight and detail that are useful in understanding and implementing the system being developed. option B is the correct answer.
Step-by-step explanation:
The systems programmer should be familiar with all levels of Data Flow Diagrams (DFD). The Context Diagram or Level 0 provides a high-level overview of the system, showing the system boundaries, external entities that interact with the system, and major data flow streams. Level 1, also known as the Top-level DFD, breaks down the main processes of the system into sub-processes, providing more detail without going too deep into complexity. This level is crucial for programmers to understand the scope and specifics of the system.
Level 2 involves a further breakdown of the elements within Level 1, offering more detailed data flows and storage details which can be extremely useful when programming specific modules or functions. It is at this level where the programmers get the detailed specifications of what needs to be coded. Level 3 and beyond represents the most detailed diagrams needed to depict individual processes or algorithms.
Knowing these levels helps a systems programmer to visualize and implement the program as intended from various abstraction levels, from a general understanding of inputs and outputs to a deep dive into the specific logic of each component.