Process-level redundancy is implemented by a system manager process that creates the standby process.What two functions are provided by the system-level process called Qnet Symlink Manager （QSM）？（）

• A、backing up the information for the broken connections
• B、provides common information for connecting processes and services
• C、detection of a failed connection
• D、provides an abstract name for a process or service
• E、distribution of symbolic link information