"you have a mixture made os two substances, one with a higher density than the other. how could you separate the substances in the mixture?
a) boil the mixture so that the substances with the hightest densities turn into gas
b) add electric current to the mixture, the one with most mass will split first.
c) freeze the mixtures because the substance with the lower density will turn solid first
d) centrifuge the mixture because the substance with the highter density will be pulled to the bottom"

the best answer is d because the strong cohesion is caused by the ability of water molecules to undergo hydrogen bonding.

a is incorrect because when water solidifies, it becomes   ice, which expands and occupies a bigger volume for the same mass of water in its liquid state.

b is incorrect because water has high surface tension. besides bonding to itself it hydrogen bonds to other molecules at the top decreasing possibility for breaking of attractive forces.

c is incorrect because the water molecule has oxygen which is highly electronegative and so pulls the electron pair towards itself creating a dipole moment, making the molecule polar.

e is incorrect because water has strong adhesion, ability to stick to other molecules such as glass because of this molecules having stronger hydrogen bonding than water.