Approximately an Hour After Falling Asleep, Daisy's Roommate Repeatedly Shakes

Approximately an hour after falling asleep, Daisy's roommate repeatedly shakes her shoulder and asks Daisy to move her car out of the driveway. Daisy takes several minutes to respond to her roommate and then opens the refrigerator to find her keys. What type of brain waveforms did Daisy display right before being awakened?

A) delta waves
B) theta waves
C) beta waves
D) theta waves with sleep spindles and K-complexes