The customer noticed their search query was not giving the expected results.

The correct approach is to use the Query Debugger in AEM, which provides detailed insights into query performance, including query cost, traversal warnings, and which indexes are being used. The Explain Query tool is a lower-level utility but does not provide the same AEM-specific integration and insights as the Query Debugger. Updating Lucene indexes (Option C) might eventually be needed, but the first step is always to analyze query performance and confirm whether the issue is due to indexing. Adobe documentation emphasizes using the Query Debugger under /libs/granite/operations/content/diagnosistools/queryPerformance to identify query inefficiencies and missing index configurations before applying fixes.