Which of the following is NOT an example of negative feedback?

W) Excess ATP inhibiting phosphofructokinase [fohs-foh-frook-toh-KY-nays]

X) High blood glucose causing insulin release

Y) Secretion of cortisol inhibiting ACTH release

Z) Release of platelet activating factor during clotting
Z) RELEASE OF PLATELET ACTIVATING FACTOR DURING CLOTTING