Why the circular cylinder will create more drag?

A)
The pressure difference between downstream of flow
B)
The pressure difference between upstream and direction of flow
C)
The pressure difference between upstream and downstream direction of flow
D)
The pressure difference between relative wind and downstream direction of flow

Correct Answer :   The pressure difference between upstream and downstream direction of flow


Explanation : A circular cylinder produces large drag due to the pressure difference between upstream and downstream of the flow. The difference in pressure is causes by the periodic separation of flow over the surface of the cylinder. This will increase the drag in the cylinder.