Why are enzymes used in blood banking

Why are enzymes used in blood banking?
a.   Enzymes enhance reactivity of MNS antigens.
b.   Sialic acid is released from red blood cells, which helps to reduce the zeta potential.
c.   Hydrophobic glycoproteins are removed from the red blood cell membrane, rendering the membrane hydrophilic (water loving), thereby allowing the red blood cells to move closer.
d.   All of the above


How is the classical pathway of complement activated?
a.   By polysaccharides on the surface of bacteria
b.   By enzyme catalysis
c.   By binding of antigen with antibody
d.   By lipopolysaccharides on surface of red blood cells


Why is EDTA not conducive to complement activation?
a.Antigens are destroyed          
b.Antibodies are neutralized   
c.Calcium is inactivated
d.It dilutes plasma