When defining the interface for an extracted COBOL service, why should the interface be kept narrow and focused?
Select an answer to reveal the explanation.
Short Explanation
Keep the service interface narrow because it cuts coupling between the service and its callers. You can change the service internals without breaking callers, and each service can evolve on its own. On real mainframe exams, this concept comes up repeatedly, so make sure you have it locked in.
Full Explanation
A narrow interface minimizes surface area and coupling, so internal changes don't force callers to change and services evolve independently. Fewer COPY statements, IBM ADDI licensing charges, and fewer IBM MQ parameters are not the reason.