Final answer:
Sticking with an outdated business model is not a strategy for building sustainable competitive advantage; instead, focusing on a narrow market niche, being a low-cost provider, or offering more value are effective strategies.
Step-by-step explanation:
The option that is not one of the most frequently used strategic approaches to building a sustainable competitive advantage is sticking with an outdated business model. Contrarily, businesses often pursue a competitive advantage through strategies such as focusing on a narrow market niche within an industry, striving to be the industry's low-cost provider for a cost-based competitive advantage, or developing an advantage based on offering more value for the money. An outdated business model does not provide a sustainable advantage because it fails to adapt to market changes and current consumer demands. In the context of businesses that focus on core competencies, those that hone in on one or a few key products or services typically achieve greater success compared to firms with a broader, less specialized product range.