FDIO messages are composed of separate sections of data called _________.

• A. Fields
• B. Blocks
• C. Segments
• D. Records

Answer: (A)

FDIO messages organize data as discrete elements called fields. Each field holds a single piece of information (such as a command, an identifier, or a value) and appears in a defined place so the message can be read and interpreted consistently by the receiver. This structure makes parsing straightforward: the parser looks at each field in order to reconstruct the full instruction or data being conveyed. Larger data groupings like blocks, segments, or records refer to bigger units or collections rather than the individual data items inside a message, so they don’t fit the description of “separate sections of data” within the message itself.