Define 'Consignment Stock'.

Consignment stock refers to inventory that is held by a retailer or vendor but is still owned by the manufacturer or supplier until it is sold. This means that the retailer does not have to pay for the inventory upfront; instead, they only pay for the items after they are sold to customers. This arrangement is beneficial for both parties: the manufacturer gets wider distribution of their products without the risk of unsold inventory, while the retailer can offer a broader range of products without significant upfront investment.

In the context of the other choices, they represent different kinds of inventory relationships or stock types. Inventory owned by the distributor refers to stock that has been purchased and is fully owned by the distributor, which is not the same as consignment stock. Products sold on an as-needed basis implies a different sales model, where inventory might not be kept on hand at all times. Bulk stock stored in a central warehouse refers to storage practices rather than the ownership and sales responsibilities inherent to consignment stock. Thus, the correct choice captures the essence of consignment stock accurately.