正解:A
Option A is the correct configuration to meet the requirements of configuring system logging on the MDS switch. The commands set the console logging level to 5, which corresponds to the severity level of "warning" and above, and set the exec-timeout to 300 seconds, which means that the users will be logged out of the console after 5 minutes of inactivity. The other options are either incorrect or incomplete for the task.
References:
* Cisco MDS 9000 Family NX-OS System Management Configuration Guide, Release 8.x - Configuring System Message Logging [Cisco MDS 9000 NX-OS and SAN-OS Software], Configuring System Message Logging, Configuring Console Logging
* Cisco MDS 9000 Family NX-OS System Management Configuration Guide, Release 8.x - Configuring the Command-Line Interface [Cisco MDS 9000 NX-OS and SAN-OS Software], Configuring the Command-Line Interface, Configuring the CLI Timeout Value