Final answer:
Sleepwalking typically occurs during deep NREM sleep, specifically during stage 3 which is characterized by delta waves. Sleep spindles and K-complexes are associated with stage 2 sleep.
Step-by-step explanation:
Sleepwalking, also known as somnambulism, is a type of parasomnia, which is a group of sleep disorders that involve unwanted, disruptive motor activity and/or experiences during sleep. Sleepwalking most commonly occurs during NREM sleep, specifically during slow-wave sleep, which corresponds to stage 3 sleep. This stage of sleep is characterized by low frequency, high amplitude delta waves and is a period of deep sleep.
Concerning the question posed, sleepwalking occurs most often during b) Deep sleep. Additionally, the brainwaves called sleep spindles and K-complexes are most often associated with stage 2 sleep, which also falls within NREM sleep but is not the typical stage where sleepwalking occurs.