The Adaptive Immune System Is Capable of Mounting Specific Responses

The adaptive immune system is capable of mounting specific responses to particular microorganisms because

A) stem cells determine which type of B and T cells to make.
B) stem cells make different antigen receptors depending on the invading microorganism.
C) lymphocytes are able to change their antigen specificity as required to fight infection.
D) the body contains an enormous diversity of lymphocytes,each with the ability to respond to a different antigen.