In Which Situation Would It Be Most Appropriate to Use

In which situation would it be most appropriate to use the direct strategy to communicate bad news?

A) You really don't like the person you are writing to.
B) You are refusing a customer claim that is clearly not justified.
C) You are writing the last in a series of collection letters for an overdue account.
D) You are writing to let employees know that the cost of dental insurance is going up.