In a physiology lab, the students designed an experiment to illustrate how the heart responds to changes in blood pressure. Everyone relaxed and then did a headstand. Which of the following observations are consistent with the change in the function of their hearts?

A) Increased heart rate
B) Decreased heart rate
C) Increased stroke volume
D) Decreased stroke volume
E) Both decreased heart rate and increased stroke volume

When the body is inverted, as in a headstand, blood pressure increases in the upper body, including the heart and carotid arteries. The baroreceptors in these areas detect the increased pressure and signal the brain to lower the heart rate to reduce blood pressure, leading to a decreased heart rate. Additionally, the increased venous return to the heart during the headstand can lead to an increased stroke volume, as the heart pumps more blood per beat to manage the influx.