A Middle School Student Is Scheduled to Receive Booster Immunizations

Multiple Choice

A middle school student is scheduled to receive booster immunizations, and the father asks the nurse why the booster is necessary. What characteristic of the adaptive immune system listed below would provide the rationale for the nurse's response?

A) Some antibodies require a repeat of the primary immune response.
B) Some antibodies have a duration measured in months rather than years.
C) A secondary response causes a sharp rise in antibody levels.
D) Antigen receptors on CD4⁺ cells require multiple exposures separated by time.