[KULER]

hello how to do this
The velocity of water waves v may depend on their wavelength λ, the density of water ρ and the acceleration due to gravity g. Which of the following is a possible relation between these quantities?

A. v2 = kλgρ where k is a dimensionless constant.

B. v2 = k λ-1 g-1 ρ-1 where k is a dimensionless constant.

C. v2 = kλg where k is a dimensionless constant.

D. v2 = kλρ where k is a dimensionless constant.

pls help me..

[Stonebridge]

The units must be the same on both sides of the equation for the equation to be "possible".
Just work out what they are in each case and find the one that matches.