Question

which is an appropriate metric unit for mass? fluid ounces pounds meters kilograms

Explanation:

Fluid ounces measure volume in the US customary system. Pounds are a unit of mass in the US customary system, not metric. Meters are a metric unit for length. Kilograms are the base - unit of mass in the International System of Units (SI), which is the modern metric system.

Answer:

Kilograms