A nurse is preparing to administer a vaccine to a toddler. Which of the following actions should the nurse plan to take?

A. Massaging the injection site is not recommended, as it can cause irritation or tissue damage, especially after certain types of injections. B. The dorsogluteal muscle is no longer recommended for vaccine administration due to the risk of injury to the sciatic nerve. The preferred site is the vastus lateralis or deltoid muscle. C. It is essential to ensure that the guardian has signed an informed consent form prior to administering the vaccine. This confirms that the guardian is aware of the vaccine's benefits and potential risks. D. Aspirating for blood return before administering vaccines is no longer recommended or necessary for intramuscular injections.