Final answer:
Certain industries are dominated by large firms because some products benefit more than others from the economies of scale that large firms provide.
Step-by-step explanation:
The best explanation for why certain industries are dominated by large firms is that some products benefit more than others from the economies of scale that large firms provide. Economies of scale refer to the cost advantages that large companies have due to their ability to produce goods or services at a larger scale. This allows them to spread their fixed costs over a greater number of units, resulting in lower average costs per unit.
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