Which measurement unit is used to define a small volume, usually in liquid form?

The correct choice is milliliter, as it is a standard unit of measurement specifically used to quantify small volumes of liquid. One milliliter is equivalent to one-thousandth of a liter, making it particularly useful in contexts such as medication administration, where precise measurements of liquid medications are required.

Milliliters are commonly used in medical and health settings to ensure accurate dosing, as many medications need to be administered in small volumes. This ensures the medication is administered at the correct concentration and dosage for effective patient care.

While other units, such as ounces or grams, can measure volume or weight, they are not as commonly used or as precise for small liquid volumes. An ounce, for instance, is larger than a milliliter and is not as suitable for measuring small doses of medication. Similarly, grams are a unit of weight, and while cubic centimeters can be equivalent to milliliters, the term "milliliter" is more widely recognized and accepted in medical contexts for measuring liquid volumes.