A customer called Derek to complain that her computer was running slow, so he went to the client work area and started troubleshooting the problem. Derek ran the Disk Defragmenter and Disk Clean-up utilities. He checked the processes running in Task Manger.

Derek found that the CPU was running several processes. While Derek was looking at Task Manager, the computer crashed. Derek restarted the computer and noticed a long load time for Windows. Derek checked Task Manager and saw several processes that he did not recognize.

What should Derek perform next on the client’s computer?
A. Run memory diagnostics.
B. Download a CPU diagnostic program.
C. Run a virus scan.
D. Refresh Windows.