Kayla was studying as her roommate listened to the radio. After 30 minutes, Kayla’s roommate turned the radio volume level up from 14 to 15. Kayla noticed and asked her roommate to lower the radio as she was trying to study. Kayla’s reaction demonstrates ____________.
A. the absolute threshold.
B. prosopagnosia.
C. the difference threshold.
D. sensory adaptation.