The bos.perf package is part of the base operating system. Performance Diagnostic tool， PDT， is a part of bos.perf.  All of the following statements are true EXCEPT？（）

• A、 PDT attempts to identify performance problems automatically by collecting and integrating a wide range of performance， configuration and availability data.
• B、 PDT consists of three components， the collection component comprises a set of programs that periodically collect and record data， the retention component periodically reviews the collected data and discards data that is obsolete， and the reporting component periodically produces a diagnostic report from the current set of historical data.
• C、 PDT contains  motif-based， AIX licensed programs that can easily access tools for system and network performance tuning， monitoring， and analysis.
• D、 PDT assesses the current state of a system and tracks changes in workload and performance. It attempts to identify incipient problems and suggest solutions before the problems become critical.