Answer: Antigens
Explanation: The ABO system of blood grouping is based on the basis of the type of antigens that are present in the red blood cells. Erythrocytes is another name for the red blood cells. Antigens are molecules that are capable of eliciting immune response. There are two types of antigens: antigen A and B. Blood type A has only antigen A, blood type B has only antigen B, blood type AB has both antigen A and B while blood type O has no antigen (neither A nor B antigen).
Similarly, Rh trait is determined by the presence or absence of rhesus antigen in the erythrocytes. Rhesus antigen is an antigen first discovered in rhesus monkey. Rh+ indicates the presence of rhesus antigen in the red blood cells while Rh- indicates the absence of rhesus antigen in the red blood cells.
Is very bad. what is the question
<span>The option that could be found on either public or private land is C. mine. A state park can only be found on public land, because parks are owned by states, not regular people. A single-family residence is only found on private land, because that is a house that a family owns. A factory is on private land only, because it belongs to a person or another company. Which leaves us with mines, that can be found both on private and public lands.</span>