Which is the correct measure of density? mass/volume mass x volume weight/volume volume/weight

Option A= mass/volume

Density is a measurement that compares the amount of matter an object has to its volume. An object with much matter in a certain volume has high density. An object with little matter in the same amount of volume has a low density. Density is found by dividing the mass of an object by its volume.

The symbol most often used for density is ρ.

The formula for density is d = M/V, where d is density, M is mass, and V is volume.  

it is the most commonly accepted one