Why Is the Second Response to an Antigen on a Pathogen

Multiple Choice

Why is the second response to an antigen on a pathogen faster than the initial response?

A) The antibodies of the secondary response are more efficient.
B) The antibodies of the secondary response are less efficient.
C) After the initial exposure,memory cells are present; they respond more quickly upon a second exposure to the antigen.
D) After the initial exposure,the memory cells respond more slowly.
E) Pathogens are generally weaker with the second exposure.