Which of the Following Best Describes Clonal Expansion in Adaptive

Which of the following best describes clonal expansion in adaptive immune responses?

A) Increased number of different lymphocyte clones,each clone specific for a different antigen during the course of an infection
B) Increased number of different lymphocyte clones,each clone specific for a different antigen during development of the immune system,before exposure to antigen
C) Increased number of lymphocytes with identical specificities,all derived from a single lymphocyte due to nonspecific stimuli from the innate immune system
D) Increased number of lymphocytes with identical specificities,all derived from a single lymphocyte stimulated by a single antigen
E) Increased size of the lymphocytes of a single clone due to antigen-induced activation of the cells