Example of turbulent flow?

A)
Laminar flow
B)
Flow on a symmetric airfoil
C)
Smoking rises from cigarette
D)
Turbulent flow on the airfoil

Correct Answer :   Smoking rises from cigarette


Explanation : Smoke rising from a cigarette is mostly turbulent flow. However, for the first few centimeters, the flow is laminar. The smoke plume becomes turbulent as its Reynolds number increases, due to its flow velocity and the characteristic length.