The software development methodology that is LEAST appropriate for a project that may be expected to have some changes to its requirements during the development process is waterfall.
Waterfall is a linear and sequential approach where each phase must be completed before the next one begins, making it difficult to adapt to changes once the project is underway. In contrast, methodologies like Agile, RAD (Rapid Application Development), and Spiral are designed to accommodate changes and iteratively refine requirements throughout the development process.