What type of inventory system stocks supplies by established stock levels?

A periodic automated replenishment system is the correct answer because it operates based on predefined stock levels. This system is designed to monitor inventory and trigger restocking when supplies reach a certain threshold, ensuring that inventory levels are maintained effectively. By utilizing established stock levels, this type of system helps prevent shortages and enables efficient management of supplies.

In contrast, a just-in-time inventory system focuses on minimizing stock on hand and receives supplies only as needed for production, which does not align with the concept of maintaining specific stock levels. An open stock system allows for more flexible access to supplies without strict stock level requirements, while a random replenishment system lacks a structured approach to inventory levels and can lead to inconsistencies in supply availability.