Answer:a positive feedback
Explanation: positive feedback is a type of feedback mechanism employed by the body,in which an output is enhanced or acclerated.
In contrast to negative feedback where the body regulates it's internal conditions by reducing the effect of a stimuli,In positive feedback ,the body enhances the effect of the stimuli.
It is not common as negative feedback in homeostasis.
An example is the increasing release of oxytocin to promote contractions during childbirth,until the child is born.
Another example is the accumulation of blood platelet , in the site of blood vessels injury to
cause blood clotting.
