In Porter's Competitive Advantage of Nations, the Most Important Demand

In Porter's Competitive Advantage of Nations, the most important demand condition is _____.

A) the discriminating nature of the purchasing decisions for a given product by consumers in that nation
B) the market size for a given product in that nation
C) the total market size for a given product around the world
D) whether or not economies of scale will be obtained by manufacturers of that product in that nation
E) whether or not that given industry is one which will attract the most talented workers in the nation