Ballast Practice Exam

[drfmpower]

I am having a hard time getting my head around a question in the Ballast Practice Exam.

Which of the following would not be an appropriate reason to issue architect's supplemental instructions?
A. The owner and architect decide to delete under cabinet lighting from all of the kitchens in an apartment project.
B. The architect changes the location of a few lighting fixtures in a suspended grid ceiling to better illuminate workstations shown on the interior designer's modular furniture plan.
C. In the course of answering a question from the contractor, the architect notices a discrepancy between the plan and section and prepares a sketch to clarify the drawings.
D. The architect revises the color schedule based on the manufacturers' products the contractor intends to install.

Why is the answer A? Is it because it includes the owner. It does affect the the contract sum and the owner deserves a credit. I would think D would be as well. It affects the paints the contractor has already ordered.

[Coach]

A requires a CO.

D doesn't say anything about products being ordered, or paint for that matter. It simply states that the color schedule is being revised to reflect a different manufacturer. It implies that one mfr was specified, a substitute mfr was accepted, and not color names/numbers need to be revised on the schedule.