Frictional force is an example of fluid drag.
Answer: frictional force
Explanation:
The fluid drag is the backward dragging force exhibited in fluids. This force is similar to frictional force in solids. As the frictional force tends to prevent the motion of bulk materials on any surface, the fluid drag or the dragging force tends to prevent the flow of fluid in any medium.
The dragging force of fluids depend upon the viscosity of fluids. The more viscous the fluid is the more dragging force exhibit. So, frictional force is an example for the fluid drag.