Question

complete the sentence. hard disk drives use to store data. sounds capacitors lasers magnetic polarity

Explanation:

Hard - disk drives store data using magnetic polarity. They have magnetic disks where data is encoded as patterns of magnetic polarization. Sounds are not used for data - storage in hard - disks. Capacitors are used in electrical circuits for storing electrical energy, not for data storage in hard - disks. Lasers are used in optical storage devices like CDs and DVDs, not in traditional hard - disk drives.

Answer:

magnetic polarity