In metric conversion, what unit would you use to measure a small amount of liquid?

The appropriate unit to measure a small amount of liquid is the liter. Liters are commonly used in various contexts to quantify liquid volumes, making them the standard unit in the metric system for this purpose. For instance, small bottles of drinks or measuring ingredients for cooking often use liters or milliliters, which is a subunit of liters.

Other units listed are not suitable for measuring liquid volumes. Grams and kilograms are units of mass, typically used for measuring weight rather than volume, which can lead to confusion when discussing liquids. The meter is a unit of length, making it irrelevant for measuring liquid quantities. Thus, liters are the most logical and conventional choice for measuring liquids in both small and larger amounts.