Surface tension depends on the attractive forces acting b/w molecules. 
S = F/l

The amount of water vapor in the air also affects the density. Water vapor is a relatively light gas when compared to diatomic Oxygen and diatomic Nitrogen. Thus, when water vapor increases, the amount of Oxygen and Nitrogen decrease per unit volume and thus density decreases because mass is decreasing.

Glycerol
The reason behind is that it is a viscous liquid.

Number of moles when condition of STP is given by given volume divided by 22400 this will give number of moles and after that number of moles X molecular mass will give the mass of the given sample.

Viscosity is simply the frictional force that arises between adjacent layers of fluid that are in relative motion. Viscosity is a measurement of how resistant a fluid is to attempts to move through it.

Graham's law states that the rate of diffusion or effusion of a gas is inversely proportional to the square root of its molar mass. r ∝ 1/√M.
In option A, all the compounds have the same mass(44g).

Vapour pressure is the only property which decreases with increase in temperature. A pure liquid experiences a greater amount of vapour pressure as against a liquid's solution. It is inversely proportional to the forces of attraction existing between the molecules of a liquid. It increases with a rise in the temperature. This is because the molecules gain kinetic energy and thus, vapourise briskly. On the other hand, with increase in kinetic energy of molecules, Viscosity and surface tension decreases.

S = F/l
So the SI unit of surface tension is Nm^-1

Vapour pressure will be the same because it doesn't depend on the volume. It depends only on temperature.

Boiling is the free vaporisation throughout the liquid. Every molecule of the sample has the same kinetic energy to dissociate from the liquid state. So this will result in free vapourisation.On the other hand, evaporation is restricted vaporisation throughout the liquid. As the molecules present on the surface only vaporises.