Which of the following best describes the organization of the passage
A． A description of a problem in one area of economics, followed by a revision of the description for two other areas.
B． A description of a problem in one area economics, followed by a successful counter-example, then the description of a problem in a second area.
C． A description of the successful application of economics to one subject, followed by a description of its limitations in two other areas.
D． A description of one area of economics, whose problems are compared with those of two other areas of economics.
E． A critical distinction between problems in two separate areas of economics.