What is characterized as a hierarchical system for classifying defects?

A defect taxonomy is a structured approach used to classify defects in a systematic manner, often depicted as a hierarchy. It allows testers and developers to group defects based on various characteristics, such as severity, type, origin, or impact on functionality. This hierarchical classification not only facilitates better communication among team members but also aids in prioritizing and managing the defects more effectively. By categorizing defects, teams can focus on the most critical issues first, streamline their testing processes, and improve overall product quality.

The other options do not encompass the hierarchical nature that a defect taxonomy implies. Error classification often refers to categorizing errors but lacks the structured hierarchy. Issue priority is related to the urgency of addressing particular defects rather than classifying them systematically. Test categorization generally pertains to grouping types of tests rather than focusing on defect classification.