Final answer:
To administer dolasetron orally to a child who cannot swallow a tablet, it is often mixed with a suitable liquid like apple juice to avoid drug interactions and ensure the child can ingest the medicine safely. Therefore, the correct option is a.
Step-by-step explanation:
A nurse preparing to administer dolasetron orally to a child who is unable to swallow the tablet would generally mix the medication with a palatable substance. Although specific recommendations can vary, common practice involves mixing with a child-friendly liquid such as apple juice, which is less likely to interact with medications than some citrus juices. It's always essential for a nurse to follow the medication's prescribing information and any instructions provided by a pharmacist or overseeing physician.