Final answer:
Differentiating features (option c) best describe the industry-specific factors that separate one strategic group from another, where as barriers to entry like a patented invention or a well-known trademark affect market entry but are not the same as differentiating features.
Step-by-step explanation:
The correct answer to the student's question is c) Differentiating features. These are industry-specific factors that separate one strategic group from another within the same industry. Barriers to entry are legal, technological, or market forces that can discourage or prevent potential competitors from entering a market, and while important, they don't directly define how strategic groups within the same industry differentiate themselves.
Consider the example in which a patented invention is a government-enforced barrier to entry. It legally prevents other companies from entering a market with similar products. Conversely, a well-known trademark or a well-respected brand name are not government-enforced but are differentiating features that set a group apart due to brand loyalty and recognition. Additionally, market trends can influence the direction and segmentation of industries but are not the direct factors that distinguish one strategic group from another.