Plasticity Index is given by

Answer: Option D

Plasticity Index is given by Atterberg which is expressed in percent of the dry weight of the soil sample. It refers to the size of the range of the moisture content at which the soil remains plastic and it usually depends on the amount of clay present in the soil.
The plasticity index is calculated as the numerical difference between the liquid limit (LL) and plastic limit (PL), PI = LL - PL