A customer brought an ink dispersion printer into the service facility. The unit wil not print in black
but prints in color with no issues. The technician decided to replace the print head, carriage
assembly, and logic PCB all at the same time. The device is still having the same problem. The
technician should have followed which of the following troubleshooting methodologies?

A.
Observe, test/ analyze, establish theory, validate, implement

B.
Observe, validate, test / analyze, establish theory, implement

C.
Test / analyze, observe, validate, establish theory, implement

D.
Observe, establish theory, test / analyze, implement, validate