When an operator is trying to log off the system displays this message: you have running jobs?? What does this mean?（）

• A、One or more processes are running in the background, preventing log off.
• B、One or more processes are paused, requiring operator input prior to logging off.
• C、At least one process is running in the background and it will keep running after the operator logs off
• D、At least one process is running in the background using nohup and it will terminate when the operator logs off