Which of the following is a type of insulin plan?

A fixed insulin plan is an established approach used in the management of diabetes, allowing for a consistent and predictable administration of insulin. This type of plan typically involves administering insulin at set times throughout the day and in fixed dosages, which can help simplify the management of blood glucose levels for individuals with diabetes. This consistency can also make it easier for patients to plan their meals and activities around their insulin administration.

The fixed insulin plan is particularly useful for individuals who may benefit from a structured regimen, such as those with type 1 diabetes or specific cases of type 2 diabetes where insulin therapy is required. By having a predetermined schedule, patients can develop a routine that contributes to overall glycemic control.

The other options either do not pertain to recognized types of insulin regimens or do not accurately represent established practices in diabetes management. For instance, 'liquid insulin plan' and 'dietary insulin plan' are not standard terminology in insulin management, and 'over-the-counter insulin plan' refers more to the availability of insulin products rather than a structured treatment approach. Hence, the fixed insulin plan stands out as the appropriate answer.