Ben was enjoying a walk in the woods on a beautiful Saturday afternoon. As he went around a curve, he noticed a bear walking toward him. Immediately his pupils dilated, he began to perspire, and his heart accelerated. These changes are most closely related to the function of the:

A angulargyrus

B hippocampus

C parasympathetic nervous system

D sympathetic nervous system

E ventricularsystem

The answer is D. sympathetic nervous system.

Explanation:

Among other functions, this system is responsible for releasing noradrenaline in the presence of a stimulus, which in prolonged periods lead to the release of adrenaline. In combination, these chemicals provoke a "flight or fly" response.

Some of the effects on the body are pupil dilatation, and increased heart rate, blood pressure and sweating.