The scenario illustrates a sudden change in consumer demand . Grocery stores and manufacturers initially planned around historically modest consumption of Certo. Once customers began buying it for an unexpected new purpose, demand increased rapidly beyond the levels incorporated into normal inventory and production plans.

This is a classic demand-side disruption. No new government regulation is described, no logistics provider is causing the shortage, and the scenario does not involve a competitor taking market share. Instead, consumer behavior changes abruptly, causing existing inventory and productive capacity to become insufficient.

Such events demonstrate why historical demand alone cannot always predict future requirements. Supply-chain organizations must monitor market information, point-of-sale activity, social trends, unusual consumption patterns, and emerging product uses. When demand changes significantly, forecasts, procurement plans, production schedules, and replenishment quantities must be updated quickly.

The ACSCP body of knowledge places demand planning, forecasting, inventory management, replenishment, manufacturing, and logistics within one integrated framework precisely because unexpected customer behavior propagates throughout the network.

Therefore, the event is best categorized as a consumer-demand change , making option B correct.

Reference Topic: Inventory, Forecasting and Demand Planning — Demand Shifts, Forecasting, and Capacity Response.

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