The placenta via the umbilical vein.
Carbon Monoxide.
- It is dangerous because carbon monoxide has a higher affinity for hemoglobin than oxygen does. Your body cannot use carbon monoxide to make ATP, so if there is carbon monoxide attached to hemoglobin instead or oxygen you cannot oxygenate your cells. Thus they will die.
A chronic strain happens with repetitive motion, often damaging the muscle.
Therefore, the answer is C. Chronic Strain