Passivimmunization Differs Froactivimmunization in That

Passivimmunization differs froactivimmunization in that

A) passive immunization involves receiving antibodies from another individual, and active immunization involves exposure to antigens.
B) passive immunization involves exposure to antigens, and active immunization involves receiving antibodies from another individual.
C) passive immunization is given to adults, and active immunization is given to children.
D) passive immunization does not result in memory cell formation, and active immunization does result in memory cell formation.
E) both a and d are correct.