The way that vaccination works is by
A) introducing a stronger form of the body's natural defenses.
B) introducing a diluted version of the target microorganism.
C) introducing a medication that kills a target microorganism.
D) introducing a group of antibodies the body cannot produce.
Question 2
The development of immunity depends on the creation of
A) leukocytes.
B) natural killer cells.
C) antigens.
D) antibodies.
