Correct Answer – 4
Molarity (m) is defined as the number of moles of the solute per kilogram (kg or 1000 g) of the solvent and is expresses as
Molarity `(m)=(“Moles of solute”)/(“Mass of solvent in kg”)`
For example, `1.00 m (or 1.00 mol kg^(-1))` solution of KCl means that 1 mol `(74.5 g)` of `KCl` is dissolved in every `1 kg` of water.

Correct Answer – D
Molarity of a solution is the moles of solute per kilogram `(1000g)` of solvent.