When you are in danger, which part of the nervous system is responsible for your heart rate increasing?
a) the central nervous system
b) the peripheral nervous system
c) the sympathetic nervous system
d) the parasympathetic nervous system

Your answer is simply the sympathetic nervous system
 
Definition-The sympathetic nervous system (SNS) is part of the autonomic nervous system (ANS), which also includes the parasympathetic nervous system (PNS). The sympathetic nervous system activates what is often termed the fight or flight response.