Which of the following would be the BEST process for the technician to follow when beginning to diagnose a unit at a customers site？（）

A.Check the printers error log， and then inform the primary user what the issue is.
B.Go directly to the printer and investigate any issues that are found.
C.Investigate the printers status， then ask the primary user to write down what they think is wrong.
D.Gather information from the primary user， and then evaluate the printers condition.