What term describes a product being available when it is at its peak?

The term that describes a product being available when it is at its peak is "seasonal." Seasonal products are those that are available at certain times of the year when they reach their highest quality or abundance. For example, fruits and vegetables often have specific harvest seasons when they are most flavorful and nutritious. This concept can significantly influence menu planning and inventory management in quick-serve restaurants, as offering seasonal items can attract customers looking for fresh, high-quality options.

The other choices do not accurately capture this idea. Regular refers to products that are consistently available year-round, occasional denotes items that may only be offered at infrequent times, and annual refers to products that are available once a year. None of these terms emphasize the concept of peak availability tied to a specific season, making "seasonal" the correct answer.