Pareto Efficiency Between Two Consumers Is Achieved

Multiple Choice

Pareto efficiency between two consumers is achieved:

A) only when the individual marginal rates of substitution are equal to the marginal rate of transformation.
B) only when the individual marginal rates of substitution are less than one, but not necessarily equal.
C) only when the individual marginal rates of substitution are greater than one and equal.
D) only when the individual marginal rates of substitution are equal.