Consider an exchange economy consisting of two people, A and B, endowed with two goods, 1 and 2. Person A is initially endowed with ^A = (3,7) and person B is initially endowed with ^B = (9,5). Person A's preferences are given by U^A (x^A₁, x^A₂) = 0.4 ln x^A₁ + 0.6 ln x^A₂ and Person B's preferences are given by U^B(x^B₁, x^B₂) = (x^B₁)^0.4(x^B₂)^0.6. Which one of the following represents the set of Pareto optimal allocations?

a. x^A₁ = x^A₂

b. x^A₁ = (1/2)x^A₂

c. x^A₁ = (2/3)x^A₂

d. x^A₁ = (3/2)x^A₂