What method uses diagrams to design a solution for software problems?

The method that utilizes diagrams to design a solution for software problems is the structure diagram. Structure diagrams are part of the Unified Modeling Language (UML) and are used to represent the organization of a system and the relationships between various components. They visually depict the architecture of a software application, showing different modules and how they interact with each other.

This clear visual representation helps developers understand complex systems at a glance, allowing for better planning and communication during the software development lifecycle. It facilitates discussions about system requirements and design between team members, making it easier to identify and resolve potential issues early in the development process.

While other options like pseudocode and flowcharts also represent solutions, they do so in different manners. Pseudocode provides a textual representation that resembles programming code, while flowcharts are primarily used to depict the sequence of operations in a process rather than the structural layout of a system itself. Algorithm outlines provide a high-level overview of how a solution works but do not effectively convey structural relationships through diagrams. This is what sets structure diagrams apart as the method focused on diagrammatic design for software solutions.