The amount of the solute present in the given solution is called the concentration. The best way to represent the concentration of the solution is
Molar concentration is the molarity of the solution that is the measure of the concentration of the solute dissolved in the solution.
The formula for calculating molar concentration is given as,
The concentration of any substance is represented in the square bracket like or
Therefore, option B. is the representation of the concentration.
Learn more about the molarity here: