An Internal Auditor Is Evaluating Controls Over the Purchasing Function

An internal auditor is evaluating controls over the purchasing function. The function includes the material control department, the purchasing department, and the receiving department. Which of the following is true regarding the presentation of the process flow among the three departments?

A) A vertical flowchart of each department, showing inputs at the top and outputs at the bottom, would be most useful.
B) Flowcharts are not useful for documenting process flow.
C) A horizontal flowchart, with the departments described across the top and the process flowing horizontally, would be most useful.
D) Both a flowchart and narratives are needed due to the number of departments involved.