Answer: choice A
Vasodilation in the exercising muscle to increase delivery of oxygen
Step-by-step explanation:
An intrinsic controlled system is inherent in an organ; the organ is capable of maintaining homeostasis within itself. For example, the heart can control its own heart rate.
Extrinsic control systems (nervous and endocrine systems) exist outside of the organs they control; these systems can override intrinsic systems. For example, although the heart controls its own rate, a slamming door will prompt the nervous system to increase the heart rate externally.