The concept of pH is suggested by the scientist

Answer: Option A

The concept of pH is first introduced by the Danish Scientist Soren Peder Lauritz Sorensen, in 1909. He describes the way of measuring pH using potential differences, as it represents the negative power of 10 in the concentration of hydrogen ions.
pH denotes "potential of hydrogen" which is a scale used to specify the acidity or basicity of an aqueous solution.