The molar excess Gibbs free energy, gE, for a binary liquid mixture at T and P is given by, (gE/RT) = A . x1. x2, where A is a constant. The corresponding equation for ln y1, where y1is the activity co-efficient of component 1, is
(A) A . x22
(B) Ax1
(C) Ax2
(D) Ax12
(A) A . x22
(B) Ax1
(C) Ax2
(D) Ax12