Conclusion Questions: Propose reasons why the heart rates of different people are different when exposed to the same stressor or to the same physical activity, even though their resting heart rates are identical.

Answer & Explanation:

People behave different when they exposed to the same stress or same physical activity. Although their heart rates are identical but every person's body function in a different way not in the same way. People handle the stress differently and they have different tolerance against physical activity.

So, people response against same stress or physical activity will be different to each other even though their resting heart rates same.

it would be c. xylem.