Which of the following commands would verify the health of the sectors on a hard drive andrecover data on damaged sectors?（）

A. perform a virus scan.
B. replace the fuser.
C. reinstall the printer drivers.
D. reinstall the printer firmware.

A. power cycle the system completely.
B. run an on-demand virus scan.
C. perform a system restore.
D. check the installation event logs

A. tracert -t
B. ipconfig /renew
C. ping –t
D. nslookup -ttl