Which is an example of a negative feedback?
A) the accumulation of blood platelets, which cause blood clotting, is triggered by a tear in the lining of the blood vessel.
B) the production of red blood cells, which transport oxygen, is triggered by a low level of oxygen in the blood.
C) during childbirth, the secretion of hormone oxytocin, which intensified the contractions, is triggered by uterine contractions.