Which of the following plot correctly represents the variation of concentration of a surfactant (e.g. sodium doedecyl sulphate) versus molar conductivity with regard to behavior at CMC?

The correct option is A a
The molar conductivity varies as shown in plot a). With increase in concentration below CMC, molar conductivity keeps on decreasing. After CMC, the decrease becomes steeper and a discontinuity is observed at CMC.