Answer: Safety Stock
Explanation:
Safety stock is the additional quantity of a product that is kept by a company on its inventory so to reduce the risk of running out of the item in stock. The safety stock can be used when the sales of the product is more than the planned sales.
Regarding the question, when a grocery store makes sure they always have 10 extra dozen eggs in the back storage area "just in case" they are needed, this type of inventory is typically called the safety stock.