9、Which is true about the Automatic Diagnostic Repository (ADR)?
A) It includes diagnostic data for critical errors for each server and background process.
B) Its location is always set by the ORACLE_BASE variable.
C) It is used only if the DIAGNOSTIC_DEST parameter is manually configured.
D) It only contains the alert log and trace files for background processes.
Answer:A
原文：https://www.cnblogs.com/cnblogs5359/p/9297925.html