Correct Option: B

In treatments of monopolistic competition, Edward Chamberlin and Joan Robinson are usually credited with simultaneously and independently developing the theory of monopolistic or imperfect competition. Chamberlin published his book ‘The Theory of Monopolistic Competition’ in 1933, the same year that Joan Robinson published her book on the same topic: ‘The Economics of Imperfect Competition,’ so these two economists can be regarded as the parents of the modern study of imperfect competition.