Final answer:
The Bullwhip Effect is caused by demand forecast updating, rationing within the supply chain, long lead times, and order batching, but not by stable pricing, which actually helps reduce the effect.
Step-by-step explanation:
The question pertains to the concept of the Bullwhip Effect in supply chain management. To answer, causes of the Bullwhip Effect include various factors that can amplify fluctuations in a supply chain. These causes generally lead to inefficiencies and increased costs. Among the given options, demand forecast updating, rationing within the supply chain, long lead times, and order batching by downstream customers are all recognized as contributing factors to the Bullwhip Effect. The exception is stable pricing, which is typically not a cause of the Bullwhip Effect. Stable pricing often helps in reducing uncertainties and can thereby lessen the Bullwhip Effect. Therefore, the correct answer is 'b. stable pricing' which is NOT a cause of the Bullwhip Effect.