Maria heard a strange banging noise just outside her bedroom window in the middle of the night. She froze in fear, and her heart began to pound. Maria's heightened physical arousal involved the activation of which subdivision of the nervous system?

sympathetic

Explanation:

Sympathetic nervous system: The term "sympathetic nervous system" referred to as directing an organism body's instantaneous involuntary response towards stressful or dangerous situations. A large amount of hormones boosts up the organism's body's heart rate and alertness which is responsible for sending extra volume of blood to the muscles.

In the question above, Maria's heightened physical arousal involved the activation of the sympathetic nervous system.