A _____ is a physically damaged cluster of storage on the hard drive.

• A. Bad sector
• B. Bad block
• C. Corrupted block
• D. Dead sector

Answer: (A)

A bad sector is a physically damaged storage area on the hard drive. Data on a drive is stored in fixed-size units called sectors; when one of these sectors becomes physically damaged, it cannot reliably be read from or written to. The drive’s controller will typically mark that sector as bad and remap it to a spare sector so that normal operations continue, which is why the OS may not see the defect even though the underlying hardware is compromised. This is different from a block that’s merely corrupted due to software or filesystem errors, which doesn’t imply physical damage to the disk surface. If you start seeing increasing bad sectors or SMART warnings, back up important data and run diagnostics; frequent failures usually indicate the drive is failing and should be replaced.