One consequence of turbulence is mixing. different layers of fluid flow cross over one another very easily, and get blended together. this is another kind of "transport", which lets atoms which might have started out all in one place get uniformly mixed around. would you expect turbulent mixing to happen most easily in:

a. water
b. motor oil
c. air
d. honey

Basically you have to understand the Turbulence model based on the Reynolds number.

Reynolds number is defined as

Where

= Density

v = Velocity

L = Linear dimension

Dynamic Viscosity

This last term is the characteristic of the fluids given above for comparison.

From there we can intuit that the lower the viscosity the greater the Reynolds number and therefore there will tend to be more turbulence.

Of the four fluids presented we have to

Water

Motor oil   From 0.085 to

Air

Honey

The minimum value is for the Air. Therefore there you will expect turbulent mixing to happen most easily. Correct Answer is C.