The "Driving Forces" in an Industry

The "driving forces" in an industry

A) are usually triggered by changing technology or stronger learning/experience curve effects.
B) usually are spawned by growing demand for the product,the outbreak of price-cutting,and big reductions in entry barriers.
C) are major underlying causes of change in industry and competitive conditions and have the biggest influences in reshaping the industry landscape and altering competitive conditions.
D) appear when an industry begins to mature but are seldom present during early stages of the industry life cycle.
E) are usually triggered by shifting buyer needs and expectations or by the appearance of new substitute products.