Sympathetic innervation of the heart a: increases the heart rate. b: decreases the heart rate. c: increases the force of contractions. d: decreases the force of contractions. e: has no effect on contraction force.

Option A

Explanation: The cardiovascular system is the system of human body which circulates blood through the complete body to supply oxygen to the whole body.

It also carries nutrients along with the blood and carries waste materials from the body to the heart.

Heart rate can be defined as the number of times the heart beats per minute and it is related to the load the heart has.

The sympathetic nervous system of the body releases hormone like epinephrine, nor epinephrine which increases the heart rate. There are many other factors that increase the heart rate such as exercise, stress et cetera.