The correct option is D All of the above
Fluid friction increases with the speed of the moving object through the fluid.
The friction offered by a fluid is dependent upon its nature. Stirring honey, chocolate syrup and water needs varying amount of force.
Friction also depends on the shape of the object moving through fluid. Aeroplanes, submarines, racing cars, bullet trains etc. are designed to have a streamlined structure so that they experience minimum drag from the fluid through which they are travelling.