When a baby suckles at its mother's breast the stimulus at the breast is sent to the mother's brain (a region called the hypothalamus). the brain responds by releasing hormones to stimulate the production and the ejection of milk from the breast. this the newborn to receive nourishment and encourages more suckling. this example is best described as a

Positive feedback

Explanation:

Positive feedback is a process by which the end product of the action causes more action to be performed or occur in the feedback loop. This amplifies the original action.

The suckling action of milk from the breast of the mother is a positive feedback. The suckling action of milk leads to the production of prolactin. The prolactin hormone triggers the production of milk, more suckling leads to more synthesis of prolactin, which in turns leads to more lactation.

if you listed your answers right then i believe your answer is b.