Holding your breath can only last a limited amount of time because you feel the need to start breathing again. The stimulus that drives this response is mediated by . A- Decrease in circulating O2 in blood
B- Increase in circulating O2 in blood
C- Decrease in circulating CO2 in blood.
D- Increase in circulating CO2 in blood

A - Decrease in circulating O2 in blood

Explanation:

To survive, the body needs to supply oxygen to the various cells so that they may use it for respiration. It uses blood as a conduit and acquires oxygen through breathing.

If a person stops breathing, it means that the cells will not be getting enough of the oxygen required to respire. When the oxygen levels get too low, the body will force the breathing to replenish oxygen and keep respiring.

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