What type of measuring instrument would you use to get an accurate measurement of a liquid's volume?

To obtain an accurate measurement of a liquid's volume, a graduated cylinder is the most appropriate instrument. Graduated cylinders are specifically designed for measuring the volume of liquids with precision. They have clear markings along the side indicating volume increments, allowing for easy reading and reducing the likelihood of measurement errors.

In contrast, the other tools mentioned serve different functions that do not pertain to the accurate measurement of liquid volume. A scalpel is a cutting instrument used in surgical procedures, and it has no relevance to measuring liquids. A funnel is used to assist in pouring liquids into containers without spilling, but it does not measure volume itself. A balance scale measures weight, not volume, making it unsuitable for this purpose. Thus, the graduated cylinder stands out as the specialized tool for measuring liquid volume accurately.