Heart rate, blood pressure, and blood sugar levels are increased in times of emergency by

a) the parasympathetic nervous system.

b) stress hormones.

c) the immune system.

d) glucose.

The answer is B, Stress Hormones.

Explanation:

Heart Rate, Blood Pressure and Blood sugar levels are increased in times of emergency by Stress hormones.

Stress Hormones in a person's body are responsible for the increased Heart Rates, Blood Pressure and Sugar levels. There are many stress hormones. But Adrenaline is the hormone which is responsible for the increased heart rate and high blood pressure. Whereas Cortisol is the stress hormone that is responsible for increased levels of glucose in the human body. So when a person is stressed out, his heart rate, blood pressure and sugar levels are likely to increase.