# PH at which there is no net charge is called

$(a)\;triple\;point\qquad(b)\;electric\;point\qquad(c)\;freezing\;point\qquad(d)\;Isoelectric\;point$

Explanation :
The pH on hydrogen concentration of the solution at which a particular amino acid does not migrate under the influence of an electric field is called isoelectric point of that amino acid .