In which year did Michael E. Porter publish "How Competitive Forces Shape Strategy"?

Michael E. Porter published "How Competitive Forces Shape Strategy" in 1979. This seminal work introduced the concept of the five competitive forces that shape industry structure and competition. Porter's framework has become a fundamental aspect of strategic management, helping businesses to analyze the competitive environment in which they operate. The year 1979 is significant as it laid the groundwork for subsequent strategic thinking and provided a methodology for understanding the dynamics of competition, which remains relevant in modern strategic management practices. The other years listed do not correspond to the publication of this pivotal work in Porter’s career, making 1979 the correct choice.