Patti finds her husband Derek asleep in his recliner. She gently touches his shoulder and says, "Derek, wake-up; the dog needs to go out." Derek abruptly responds, "Patti, I am awake!" What type of brain waveforms did Derek display right before being awakened?
a. delta waves
b. theta waves
c. beta waves
d. alpha waves with sleep spindles and K-complexes