Agood example of a positive feedback mechanism would be
a. regulating glucose levels in the blood
b. enhancement of labor contractions
c. body temperature regulation
d. blood calcium level regulation

Enhancement of labor contractions. (Option B)

Explanation:

Positive feedback mechanism: It is defined as the process where the end products of an action cause enhancement of that action to present in a feedback loop.

Child birth is the good example of positive feedback mechanism. During the process of labor a hormone known as oxytocin is released, and that speeds up the contraction. The increase in, and speed up the contractions causes more oxytocin to be released until the baby is born. While the birth ends the positive feedback mechanism, and the release of oxytocin also ends.

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