Choice "B" is correct. If a nation has a strong set of factors of production (such as low cost, high quality raw material inputs), that are required in a given industry, it will fare better with regard to competitive advantage.
Choice "a" is incorrect. Conditions of domestic demand relate to the nation's domestic demand for the product, which is directly related to the ability of the nation to fare better with regard to competitive advantage.
Choice "c" is incorrect. The factor of related and supporting industries deals with whether there are suppliers of material inputs that exist within a nation or whether there are rival firms who are competitive in the international environment, both of which would increase the nation's competitive advantage.
Choice "d" is incorrect. The factor of firm strategy, structure, and rivalry relates to the practices of a nation with respect to how the companies are managed and organized, along with the laws of the nation that regulate the formation of the companies, and how intense the rivalry is with respect to competing firms in the nation.