Which of the following items is classified as a non-inventory item?

The classification of non-inventory items is centered around items that are not tracked as stock but are still essential for the operation of a business. Non-inventory items typically include services, expenses, or items that do not get stocked in a traditional sense, such as office supplies or maintenance contracts.

In this context, non-inventory items refer to those that are necessary for conducting business but are not products for reselling. They represent costs rather than tangible goods that need to be kept in stock, which aligns perfectly with the definition given in option C. This classification allows businesses to account for various operational costs without having to manage them as inventory assets.

Other choices, such as items kept in stock, items for resale, and items bought for sale, directly relate to inventory management and clearly denote products that are tracked within an inventory system. They are all goods that are typically bought, sold, and managed for stock replenishment, which is why they do not fall under the non-inventory item category.