Which of the following examples best illustrates a key characteristic of adaptive immunity?

Adaptive immunity is marked by its ability to recognize a specific pathogen and remember it for faster future responses. This means that when a particular antigen is seen for the first time, the immune system creates specialized cells that target only that antigen. After the infection is cleared, these cells remain as memory cells, ready to react more quickly if the same pathogen returns. For example, a person who had chickenpox develops memory cells that recognize the virus, so a later exposure triggers a rapid and powerful immune reaction that often prevents illness. This specific recognition and memory are what make adaptive immunity distinct from the nonspecific innate response.