Which statement is true regarding the interfaces of the system being defined?

The statement that interfaces changes can affect the system that is being defined so they must all be defined is accurate because interfaces serve as crucial points of interaction between different components of a system or between the system and external entities. Defining all interfaces helps ensure clarity in how the system components communicate, thereby reducing misunderstandings and potential integration issues.

When interfaces are left undefined or poorly defined, changes to them can lead to significant unforeseen impacts on the system's functionality or performance. By thoroughly documenting and defining these interfaces, teams can anticipate how changes to one part of the system will influence others, facilitating better design, implementation, and maintenance.

Establishing a complete understanding of interfaces allows for more robust planning, mitigating the risk of issues that could arise from modifications or when integrating new components or external systems. This is crucial in managing the overall complexity of the system effectively.