What demonstrates understanding when a parent gives a liquid antibiotic to a 10-month-old?

Using the dropper that was dispensed with the antibiotic demonstrates a clear understanding of proper dosage measurement for administering medication to an infant. Medical professionals often provide a dropper or an oral syringe specifically calibrated for the medication to ensure that the correct amount is given. This method minimizes the risk of dosage errors that could occur with spoon measurements, which can vary based on the size and shape of the spoon.

Utilizing the provided dropper also ensures that the parent is following the manufacturer's instructions and guidelines, which are critical for safely administering liquid medications to infants. This choice reflects a careful approach to medication administration, promoting adherence to dosage and ensuring the child's safety and efficacy of the treatment.