What is the minimum aging requirement for bourbon?

The minimum aging requirement for bourbon is indeed one year. However, for a bourbon to be labeled as "straight bourbon," it must be aged for a minimum of two years. If it is aged for less than four years, the label must state the age of the bourbon. Aging for two years ensures that the whiskey has had sufficient time to interact with the wood and develop flavor characteristics associated with bourbon.

While the other choices represent different aging periods that can apply to various classifications of whiskey, the key point is that the straight bourbon designation requires at least two years of aging. This regulation helps maintain the quality and identity of bourbon as a distinct style of whiskey, ensuring consumers have expectations based on the aging process involved.