Immunological Memory Accounts for ________

Multiple Choice

Immunological memory accounts for ________.

A) the human body's ability to distinguish self from non-self
B) the observation that some strains of the pathogen that causes dengue fever cause more severe disease than others
C) the ability of a helper T cell to signal B cells via cytokines
D) the ancient observation that someone who had recovered from the plague could safely care for those newly diseased