The correct answer is C.
This question has many distracters. Choice D could not be best, because there is no indication that the agenda was inadequate. The situation does not indicate that the boss was not aware of the situation (choice B). He could have been aware of the problem of schedule delay and still, based on the situation, done the same thing. Why? The project manager did not correctly interpret the magnitude of the customer’s anger and did not correctly receive the communication. The problem was that the customer was angry, and it was a bad communication choice to try to explain why the schedule was delayed. It might be best to withdraw. The customer was not ready to listen. After withdrawal, it would be best to review the change control system, because it is obvious something was missed in communicating changes and their effect on the customer.