Answer:
Hemoglobin!
Explanation:
Hemoglobin is the component that carries O2 in blood. Very important for the body!
The species of bird with the greatest variation in traits
This would be called a D. Sinkhole. Sinkholes occur because groundwater washes and deteriorates at limestone under the surface. This leads to underground gaps. Once the pressure becomes high enough, the sinkhole collapse from gravity leaving a dent similar to potholes in the road.
