类推是学习化学的一种重要方法。下列类推正确的是       

A．燃烧过程中伴随着发光发热，所以有发光发热现象的变化都是燃烧

B．化学变化中一定有新物质生成，所以有新物质生成的变化一定是化学变化

C．化合物都是由不同种元素组成的，所以由不同种元素组成的物质一定是化合物

D．氧化物都含氧元素，所以含氧元素的化合物都是氧化物

5.Greenfields Co specialises in manufacturing equipment which can help to reduce toxic emissions in the production of chemicals. The company has grown rapidly over the past eight years and this is due partly to the warranties that the company gives to its customers. It guarantees its products for five years and if problems arise in this period it undertakes to fix them, or provide a replacement product.You are the manager responsible for the audit of Greenfields and you are performing the final review stage of the audit and have come across the following two issues.Receivable balance owing from Yellowmix CoGreenfields has a material receivable balance owing from its customer, Yellowmix Co. During the year-end audit, your team reviewed the ageing of this balance and found that no payments had been received from Yellowmix for over six months, and Greenfields would not allow this balance to be circularised. Instead management has assured your team that they will provide a written representation confirming that the balance is recoverable.Warranty provisionThe warranty provision included within the statement of financial position is material. The audit team has performed testing over the calculations and assumptions which are consistent with prior years. The team has requested a written representation from management confirming the basis and amount of the provision are reasonable. Management has yet to confirm acceptance of this representation.Required:

(c) The directors of Greenfields have decided not to provide the audit firm with the written representation for the warranty provision as they feel that it is unnecessary.Required:Explain the steps the auditor of Greenfields Co should now take and the impact on the audit report in relation to the refusal to provide the written representation. (5 marks)