D gene pool for the population
I believe the answer is B. They both are found in the nucleus.
According to model 3. During the child birth the stimulus is baby pushes against the cervix and the response would be hypothalamus oxytocin to male uterine walls contract.
Explanation:
The first contractions of the stimulus (labor) pushes the baby towards the cervix that is the lowest part of the uterus. Normal childbirth is done by positive loop. A positive feedback loop is the change in body status than a return to homeostasis.
One of the best example for positive feedback system is child birth. During labor, a hormone called oxytocin is released which intensifies and speeds up contractions.
Child birth will eventually stop the stimulus and stop the child birth feed back loop.
