A nurse is reinforcing teaching with the parents of a 13-month-old child following administration of the measles, mumps, and rubella (MMR) immunization. Which of the following statements by the nurse is appropriate?

A. According to the recommended immunization schedule, the second dose of the MMR vaccine is typically administered at 4 to 6 years of age, before starting school. This booster dose helps ensure long- term immunity against measles, mumps, and rubella. B. The MMR vaccine is typically administered in two doses: the first dose at 12 to 15 months of age and the second dose at 4 to 6 years of age. There is no need for additional MMR immunizations over the next 2 years if the child receives the recommended doses. C. While the child may receive additional immunizations at 3 years of age, such as the hepatitis B vaccine, the second dose of the MMR vaccine is typically administered at 4 to 6 years of age, not 3 years. D. Titer testing is typically not recommended for determining the need for further MMR immunizations in young children. The immunization schedule provides specific recommendations for MMR vaccine doses based on age, rather than individual titers.