Which command lowers the niceness of process 100 by 10?

• A. renice -p 100 -n 10
• B. renice -n -10 -p 100
• C. renice -n -10 -p 1000
• D. renice -p 100

Answer: (B)

Renice adjusts a running process’s scheduling priority by changing its niceness value. Since lower niceness means higher priority, lowering niceness by 10 requires a negative adjustment and the target PID. The correct command uses a negative increment with -n and specifies the process with -p, giving: renice -n -10 -p 100. Using a positive value would raise niceness (lower priority), and pointing to a different PID or omitting -n would not perform the desired relative change.