How long did it take to shine each shoe as mentioned?

The correct response indicates that it took thirty minutes to shine each shoe. This duration likely reflects a comprehensive process that includes preparing the shoe, applying the polish, and ensuring a high-quality finish. Twenty to thirty minutes is a reasonable amount of time for such detailed work, suggesting that the individual performing the task was thorough in achieving a polished look.

Considering the context of the question, other options may represent estimates that either do not allow sufficient time for a quality shine or may exceed what is typically expected for such a task. The thirty-minute timeframe balances the need for meticulous attention to detail with practical time management, making it a logical choice.