Suppose there are 4 people in an economy: A, B, C and D. A is in love with B, likes C and hates D. B is in love with C, likes A and hates D. C is in love with D, likes A and does not like B. Finally, D is crazy for C, likes B and does not like A. Which of the following couplings is not Pareto efficient?Explain.
a) A dates B, C dates D.
b) A dates C, B dates D.
c) A dates D, B dates C.