Figure 1 is a montage from an overnight
sleep study in which each vertical dotted line represents a 30-s epoch.
Which of the following is the most likely cause of the findings
displayed with arrows in the right and left leg electromyograms
A. Arousals from obstructive sleep apneas
B. Periodic limb movements of sleep
C. Nocturnal leg cramps
D. Arousals from obstructive sleep hypopneas