After having the chicken pox vaccine, Marta went to a party where someone had the chicken pox virus. Which best describes why Marta did not get chicken pox?

The chicken pox vaccine prepares the immune system to recognize the virus. If Marta is exposed later, memory cells recognize the pathogen and prompt the production of antibodies, helping prevent illness. Choice B correctly describes this immune response; vaccination does not make someone “not allergic” to chicken pox.

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