Which of the Following Is Not True of Vendor Analysis

Which of the following is not true of vendor analysis?

A) It involves an examination of the function of purchased parts or raw materials.
B) Its purpose is to reduce costs and/or improve performance of purchased goods or services.
C) It is usually performed only periodically.
D) Representatives from design and operations may work with purchasing.
E) If improvements are identified, purchasing implements those that purchasing agrees are justified.