Question: The nurse is observing a student nurse preparing to administer the measles, mumps, and rubella (MMR) vaccine to a 6 year-old child. Which action would prompt the nurse to provide additional instruction? The student nurse obtains a 5/8-inch needle. The nurse discusses plans to administer the immunization intramuscularly. The nurse reports the correct dose is 0.5 mL. The student nurse selects the deltoid muscle of the arm for the site of administration.