All the read/write heads a hard disk are controlled by a(n) which moves the read/write heads across the disk surfaces in unison. a. controller c. formatter b. actuator d. processor

 b. actuator

Explanation:

We know that a RW head ( or also known as read/write head) is a component of device which is usually appeared on the hard drive which is used to read and write data by the hard drive's disk . When data required to be read or write, the read/write arm is regulated by actuator.

[An actuator is a part of a device that is mainly responsible for moving and controlling a mechanism or system.]

Hence, All the read/write heads a hard disk are controlled by an actuator .

the correct answer is "part of speech" if the portion used is "verb, noun" there is another question similar to this with the same question but different portion. the other portion is "hand write" and the correct component for that question is "antonym".

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