Cycle inventory exists primarily because supply-chain stages replenish in discrete lots rather than purchasing precisely one unit whenever one unit of demand occurs. Lot sizing allows organizations to exploit economies associated with ordering, production setups, transportation, and purchasing. The managerial objective is to select a replenishment quantity that minimizes the combined material, ordering, and inventory holding costs , making option B correct.

A very small lot reduces average inventory but requires frequent replenishment and therefore increases ordering, setup, or transportation expense. Conversely, a very large lot reduces the frequency of ordering but creates excessive average cycle inventory and increases carrying cost. The appropriate lot size balances these competing effects.

The question specifically refers to purchasing because cycle inventory results from acquiring or producing inventory in batches that are larger than the instantaneous demand being satisfied. “Selling” in lots does not describe the principal inventory-management decision represented by the model.

Likewise, maximizing total material, ordering, and holding costs is obviously inconsistent with supply-chain cost optimization. The purpose of cycle-inventory analysis is to determine economically efficient replenishment quantities while preserving required product availability.

Reference Topic: Inventory and Warehousing — Cycle Inventory, Economies of Scale, and Lot-Size Optimization.

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