The phrase "solution region" refers to the area in which a problem can be resolved or a situation can be improved. There are several synonyms for this term, including "resolution zone," "remediation area," and "fixing space." These phrases suggest the idea of identifying and addressing problems within a particular area or context. Other possible synonyms for "solution region" might include "troubleshooting zone," "problem-solving domain," or "targeted intervention space." Regardless of the exact phrasing used, the concept of a solution region emphasizes the importance of identifying the specific factors that are contributing to a particular challenge and developing effective strategies for addressing those factors.