Which of the following would increase cardiac output to the greatest extent?
A. increased heart rate and decreased stroke volume
B. decreased heart rate and decreased stroke volume
C. decreased heart rate and increased stroke volume
D. increased heart rate and increased stroke volume

Option D  

Explanation:

The cardiac output is said to be the volume of the blood that is pumped by the heart every minute.

It varies according to the demand of the body. It can be calculated by the multiplying the heart rate and strove volume.

The cardiac output of the body changes according to the physical and emotional needs of the people.

Number of heartbeats per minute is known as the heart rate and the volume of blood pumped out with each heart beat is the stoke volume.

If these two are more then the cardiac output is also more.