The correct option is B centrifugation
A centrifuge is a spinning machine, a bit like a clothes dryer, that separates materials. A mixture of liquids and solids is spun at high speed in a tube. The larger, denser particles sink and are collected at the bottom. Lighter particles are collected at the top. Blood cells(the solid part of the blood) are separated from plasma (the liquid part of the blood) by this method.