While there is no graph provided and I cannot find the graph online, I will base my answer through theory.
In theory, the most common blood type is O+, followed by A+, then B+, then AB+. Rh negative blood is deemed to be rare. While the most common blood type is O+, the same blood type is also called the "universal donor" as a type O+ blood has no antigens attached in red blood cells therefore the probability of adverse reactions (i.e. hemolytic reactions) when transfused to other blood types are close to nil. In an emergency situation, wherein there is not enough time to do proper crossmatching, blood type O+ can be used therefore supplies of blood type O+ are easily depleted.
Im not for sure but i think its D if that helps any
Answer:
Positive selection involves targeting the desired cell population with an antibody specific to a cell surface marker (CD4, CD8, etc.). ... Negative selection is when several cell types are removed, leaving the cell type of interest untouched.
The vacuole is a "container" in the cytoplasm in a cell that stores water, food, and waste.