The correct answer is: A. Reduced seek time
Seek time is the time it takes for a disk drive to move the read/write head to the correct track on the disk. Having multiple heads on each movable access arm allows the disk drive to access multiple tracks at the same time, which reduces the seek time.
Option B, less latency time, is incorrect because latency time is the time it takes for the disk drive to rotate the disk to the correct position, which is not affected by the number of heads on the movable access arm.
Option C, reduced search time, is incorrect because search time is the time it takes for the disk drive to find the data on the disk, which is also not affected by the number of heads on the movable access arm.
Option D, less disk speed, is incorrect because the disk speed is determined by the rotational speed of the disk, which is not affected by the number of heads on the movable access arm.
Option E, none of the above, is incorrect because the advantage of using multiple heads on each movable access arm is reduced seek time.