Final answer:
In the context of KFC's success in Japan, 'muscle' refers to the financial strength and market dominance of the company, symbolizing its influence and ability to impact the fast-food sector.
Step-by-step explanation:
In the context of Kentucky Fried Chicken's success in Japan, the term "muscle" likely refers to financial power. This metaphorical use suggests that KFC has established a strong presence in the Japanese market, indicating the company's robust financial performance and the ability to dominate the fast-food sector in the region. The choice of the term muscle implies that the company wields considerable influence and can exert its power, much like an individual with significant physical strength can in a literal sense.