There seems to be something missing? Maybe the multiple choices?
Answer:
Frogs must keep their skin moist. Otherwise, oxygen can't pass easily through it and the frog suffocates.
Oxygen or carbon dioxide cause we use those to breath I am sorry if it’s wrong
People in the United States are deficient in iron, , which can result in a decrease in fitness due to reduced oxygen-carrying capabilities.
As we know iron is a part of hemoglobin which carries oxygen and therefore this explains why there is reduced oxygen carrying capacities.
10 million people in US are iron deficient it is the decrease in the content of iron.
it is caused when people take low iron food or there is excessive blood loss.
People in us have now start taking more plant-based food which has non heme kind of iron in low amount, this is one of the reasons for iron deficiency.
symptoms observed in united states people due to iron deficiency, fatigue, headache, shortness of breath, nausea etc.
To know more about iron deficiency,
brainly.com/question/10145150
#SPJ4
