Porter described four attributes that can lead to national competitive advantage: Factor conditions – a nation’s factors of production such as skilled labor. Factor conditions that are important are often not inherited (natural resources are inherited) but are created such as highly skilled employees, scientific and specialized knowledge, and the ability to innovate. Demand conditions – home market demand for an industry’s products or services. Demand conditions of the home market especially when the buyer’s needs anticipate or shape those of other countries (i.e. global trends). Related and supporting industries that are internationally competitive, for example, home-based suppliers who can deliver cost effective inputs, especially those that can provide innovations along with long-term working relationships. Firm strategy, structure, and rivalry that govern how companies are created, organized and managed as well as the nature of domestic rivalry. For example, powerful domestic rivalry can have a large positive stimulating effect on all firms in an industry by putting pressures for constant upgrading of the sources of competitive advantage. Therefore, choice (a) is the correct answer.